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[PATCH v1 3/3] async postgres_fdw 60+ messages / 7 participants [nested] [flat]
* [PATCH v1 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 26 + .../postgres_fdw/expected/postgres_fdw.out | 222 ++++--- contrib/postgres_fdw/postgres_fdw.c | 615 ++++++++++++++++-- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 711 insertions(+), 174 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 27b86a03f8..1afd99cad8 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -56,6 +56,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -200,6 +201,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -213,6 +215,30 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Rerturns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 48282ab151..bd2e835d2d 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6900,7 +6900,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -6928,7 +6928,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -6956,7 +6956,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -6984,7 +6984,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7054,35 +7054,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar.f1, bar.f2, bar.ctid, bar.*, bar.tableoid + Sort Key: bar.f1 + -> Seq Scan on public.bar + Output: bar.f1, bar.f2, bar.ctid, bar.*, bar.tableoid -> Foreign Scan on public.bar2 bar_1 Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo - Output: foo.ctid, foo.f1, foo.*, foo.tableoid - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_1 Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo + Output: foo.ctid, foo.f1, foo.*, foo.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7092,35 +7098,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar.f1, bar.f2, bar.ctid, bar.*, bar.tableoid + Sort Key: bar.f1 + -> Seq Scan on public.bar + Output: bar.f1, bar.f2, bar.ctid, bar.*, bar.tableoid -> Foreign Scan on public.bar2 bar_1 Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo - Output: foo.ctid, foo.f1, foo.*, foo.tableoid - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_1 Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo + Output: foo.ctid, foo.f1, foo.*, foo.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7150,11 +7162,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo - Output: foo.ctid, foo.f1, foo.*, foo.tableoid - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_1 Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo + Output: foo.ctid, foo.f1, foo.*, foo.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7168,12 +7181,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo - Output: foo.ctid, foo.f1, foo.*, foo.tableoid - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_1 Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo + Output: foo.ctid, foo.f1, foo.*, foo.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7203,16 +7217,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append - -> Seq Scan on public.foo - Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 Output: ROW(foo_1.f1), foo_1.f1 Remote SQL: SELECT f1 FROM public.loct1 - -> Seq Scan on public.foo foo_2 - Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 + -> Async Foreign Scan on public.foo2 foo_3 Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) Remote SQL: SELECT f1 FROM public.loct1 + -> Seq Scan on public.foo + Output: ROW(foo.f1), foo.f1 + -> Seq Scan on public.foo foo_2 + Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7230,17 +7245,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append - -> Seq Scan on public.foo - Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 Output: ROW(foo_1.f1), foo_1.f1 Remote SQL: SELECT f1 FROM public.loct1 - -> Seq Scan on public.foo foo_2 - Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 + -> Async Foreign Scan on public.foo2 foo_3 Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) + -> Seq Scan on public.foo + Output: ROW(foo.f1), foo.f1 + -> Seq Scan on public.foo foo_2 + Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) +(47 rows) update bar set f2 = f2 + 100 from @@ -7390,27 +7406,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8485,11 +8507,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1) INNER JOIN (ftprt2_p1 t2)) INNER JOIN (ftprt1_p1 t3) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_1) INNER JOIN (ftprt2_p2 t2_1)) INNER JOIN (ftprt1_p2 t3_1) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8524,20 +8547,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1 - -> Foreign Scan on ftprt1_p2 t1_1 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1 + -> Async Foreign Scan on ftprt1_p2 t1_1 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2 - -> Foreign Scan on ftprt2_p2 t2_1 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2 + -> Async Foreign Scan on ftprt2_p2 t2_1 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8566,11 +8591,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1) INNER JOIN (ftprt2_p1 t2) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_1) INNER JOIN (ftprt2_p2 t2_1) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8623,21 +8649,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2 - -> Foreign Scan on ftprt2_p2 t2_1 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2 + -> Async Foreign Scan on ftprt2_p2 t2_1 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1 - -> Foreign Scan on ftprt1_p2 t1_1 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1 + -> Async Foreign Scan on ftprt1_p2 t1_1 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8672,18 +8700,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_2 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8694,13 +8723,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index bdc21b36d1..f3212aac90 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrive PgFdwScanState struct from ForeginScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,28 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection private area structure. + */ +typedef struct PgFdwConnpriv +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnpriv; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnpriv *connpriv; /* connection private memory */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +160,7 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ + bool result_ready; unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool run_async; /* true if run asynchronously */ + bool inqueue; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last waiting node in waiting queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.connpriv = (PgFdwConnpriv *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnpriv)); + fsstate->s.connpriv->leader = NULL; + fsstate->s.connpriv->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->run_async = false; + fsstate->inqueue = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,259 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipuration functions + */ + +/* + * add_async_waiter: + * + * adds the node to the end of waiter queue. Immediately starts the node if no + * node is running + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.connpriv->leader; + + /* do nothing if the node is already in the queue or already eof'ed */ + if (leader == node || fsstate->inqueue || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* immediately send request if not busy */ + request_more_data(node); + } + else + { + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->inqueue = true; + } +} + +/* + * move_to_next_waiter: + * + * Makes the first waiter be next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *ret = fsstate->waiter; + + Assert(fsstate->s.connpriv->leader = node); + + if (ret) + { + PgFdwScanState *retstate = GetPgFdwScanState(ret); + fsstate->waiter = NULL; + retstate->last_waiter = fsstate->last_waiter; + retstate->inqueue = false; + } + + fsstate->s.connpriv->leader = ret; + + return ret; +} + +/* + * remove the node from waiter queue + * + * This is a bit different from the two above in the sense that this can + * operate on connection leader. The result is absorbed when this is called on + * active leader. + * + * Returns true if the node was found. + */ +static inline bool +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.connpriv->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->inqueue) + return false; + + leader_state = GetPgFdwScanState(leader); + + /* Remove the leader node */ + if (leader == node) + { + ForeignScanState *next_leader; + + if (leader_state->s.connpriv->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.connpriv->busy = false; + } + + /* Make the first waiter the leader */ + if (leader_state->waiter) + { + PgFdwScanState *next_leader_state; + + next_leader = leader_state->waiter; + next_leader_state = GetPgFdwScanState(next_leader); + + leader_state->s.connpriv->leader = next_leader; + next_leader_state->last_waiter = leader_state->last_waiter; + } + leader_state->waiter = NULL; + + return true; + } + + /* + * Just remove the node in queue + * + * This function is called on the shutdown path. We don't bother + * considering faster way to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + else + leader_state->last_waiter = cur; + + fsstate->inqueue = false; + + return true; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } + + return false; +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuples slot to indicte EOF. + * + * If the node is asynchronous one, clear tuple slot has two meanings. + * If the caller receives clear tuple slot, asyncstate indicates wheter + * the node is EOF (AS_AVAILABLE) or waiting for data to + * come(AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* finish running query to send my command */ + if (!fsstate->s.connpriv->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* + * Fetch the result immediately. This executes the next waiter if + * any. + */ + fetch_received_data(node); + } + else if (!fsstate->s.connpriv->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* This connection is busy */ + bool available = true; + ForeignScanState *leader = fsstate->s.connpriv->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* Check if the result is immediately available */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* The next waiter is executed automatcically */ + if (available) + fetch_received_data(leader); + + /* add the requested node */ + add_async_waiter(node); + + /* add the previous leader */ + add_async_waiter(leader); + } + } /* - * Get some more tuples, if we've run out. + * If we haven't received a result for the given node this time, + * return with no tuple to give way to another node. */ if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + if (fsstate->eof_reached) + { + fsstate->result_ready = true; + node->ss.ps.asyncstate = AS_AVAILABLE; + } + else + { + fsstate->result_ready = false; + node->ss.ps.asyncstate = AS_WAITING; + } + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + fsstate->result_ready = true; + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1806,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1814,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1844,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1864,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1872,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2661,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.connpriv = (PgFdwConnpriv *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnpriv)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2748,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2799,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2998,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnpriv *connpriv; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3043,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + connpriv = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnpriv)); + if (connpriv) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.connpriv = connpriv; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3625,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3692,127 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.connpriv->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.connpriv->busy); + /* must be not-eof */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.connpriv->busy = true; + + /* Let the node be the leader if it is different from current one */ + if (leader != node) + { + /* + * If the connection leader exists, insert the node as the connection + * leader making the current leader be the first waiter. + */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.connpriv->leader = node; + } +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.connpriv->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* move the remaining tuples to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; char sql[64]; - int numrows; + int addrows; + size_t newsize; int i; snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", fsstate->fetch_size, fsstate->cursor_number); - res = pgfdw_exec_query(conn, sql); + res = pgfdw_get_result(conn, sql); /* On error, report the original query, not the FETCH. */ if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3822,75 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); + + PQclear(res); + res = NULL; } PG_FINALLY(); { + fsstate->s.connpriv->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + fsstate->s.connpriv->busy = false; + + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate a connection so that this node can send the next query + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnpriv *connpriv = fdwstate->connpriv; + ForeignScanState *leader; + + /* the connection is alrady available */ + if (connpriv == NULL || connpriv->leader == NULL || !connpriv->busy) + return; + + /* + * let the current connection leader read the result for the running query + */ + leader = connpriv->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +4004,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.connpriv = (PgFdwConnpriv *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnpriv)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4093,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4123,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4138,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4177,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4187,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4200,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4331,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4499,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4509,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +6003,42 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add an wait event only when the node is the connection leader. Elsewise + * another node on this connection is the leader. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* If the caller didn't reinit, this event is already in event set */ + if (!reinit) + return true; + + if (fsstate->s.connpriv->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index ea052872c3..696af73408 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 1c5c37b783..69c06ac6e4 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1730,25 +1730,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1790,12 +1790,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1854,8 +1854,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.23.0 ----Next_Part(Fri_Dec__6_17_12_11_2019_974)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v2 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 222 ++++--- contrib/postgres_fdw/postgres_fdw.c | 607 ++++++++++++++++-- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 703 insertions(+), 176 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index e45647f3ea..2184f7745a 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Rerturns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not any. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 62c2697920..e11e0d40a7 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append - -> Seq Scan on public.foo - Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 Output: ROW(foo_1.f1), foo_1.f1 Remote SQL: SELECT f1 FROM public.loct1 - -> Seq Scan on public.foo foo_2 - Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 + -> Async Foreign Scan on public.foo2 foo_3 Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) Remote SQL: SELECT f1 FROM public.loct1 + -> Seq Scan on public.foo + Output: ROW(foo.f1), foo.f1 + -> Seq Scan on public.foo foo_2 + Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append - -> Seq Scan on public.foo - Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 Output: ROW(foo_1.f1), foo_1.f1 Remote SQL: SELECT f1 FROM public.loct1 - -> Seq Scan on public.foo foo_2 - Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 + -> Async Foreign Scan on public.foo2 foo_3 Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) + -> Seq Scan on public.foo + Output: ROW(foo.f1), foo.f1 + -> Seq Scan on public.foo foo_2 + Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 2175dff824..7b34afa119 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrive PgFdwScanState struct from ForeginScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,28 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +160,7 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ + bool result_ready; unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool run_async; /* true if run asynchronously */ + bool inqueue; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last waiting node in waiting queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->run_async = false; + fsstate->inqueue = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,249 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipuration functions + */ + +/* + * add_async_waiter: + * + * Enqueue the node if it doesn't in the queue. Immediately starts the node if + * the connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* do nothing if the node is already in the queue or already eof'ed */ + if (leader == node || fsstate->inqueue || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* immediately send request if not busy */ + request_more_data(node); + } + else + { + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->inqueue = true; + } +} + +/* + * move_to_next_waiter: + * + * Makes the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *ret = fsstate->waiter; + + Assert(fsstate->s.commonstate->leader = node); + + if (ret) + { + PgFdwScanState *retstate = GetPgFdwScanState(ret); + fsstate->waiter = NULL; + retstate->last_waiter = fsstate->last_waiter; + retstate->inqueue = false; + } + + fsstate->s.commonstate->leader = ret; + + return ret; +} + +/* + * Remove the node from waiter queue. + * + * Results are cleared before removing leader if it is busy. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->inqueue) + return; + + leader_state = GetPgFdwScanState(leader); + + /* Remove the leader node */ + if (leader == node) + { + ForeignScanState *next_leader; + + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + /* Make the first waiter the leader */ + if (leader_state->waiter) + { + PgFdwScanState *next_leader_state; + + next_leader = leader_state->waiter; + next_leader_state = GetPgFdwScanState(next_leader); + + leader_state->s.commonstate->leader = next_leader; + next_leader_state->last_waiter = leader_state->last_waiter; + } + leader_state->waiter = NULL; + + return; + } + + /* + * Just remove the node in queue + * + * This function is called on the shutdown path. We don't bother + * considering faster way to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + else + leader_state->last_waiter = cur; + + fsstate->inqueue = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check asyncstate to tell if all tuples received (AS_AVAILABLE) + * or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* finish the running query before sending command for this node */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* Check if the result is immediately available */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* Fetch the leader's data if any */ + if (available) + fetch_received_data(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* queue the previous leader for the next request if needed */ + add_async_waiter(leader); + } + } - /* - * Get some more tuples, if we've run out. - */ if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + { + fsstate->result_ready = true; + node->ss.ps.asyncstate = AS_AVAILABLE; + } + else + { + fsstate->result_ready = false; + node->ss.ps.asyncstate = AS_WAITING; + } + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + fsstate->result_ready = true; + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1796,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1804,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1834,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1854,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1862,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2651,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2738,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2789,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2988,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3033,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3615,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3682,127 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* Let the node be the leader if it is different from current one */ + if (leader != node) + { + /* + * If the connection leader exists, insert the node as the connection + * leader making the current leader be the first waiter. + */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; + } +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* move the remaining tuples to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; char sql[64]; - int numrows; + int addrows; + size_t newsize; int i; snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", fsstate->fetch_size, fsstate->cursor_number); - res = pgfdw_exec_query(conn, sql); + res = pgfdw_get_result(conn, sql); /* On error, report the original query, not the FETCH. */ if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3812,75 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); + + PQclear(res); + res = NULL; } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + fsstate->s.commonstate->busy = false; + + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate a connection so that this node can send the next query + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + /* the connection is alrady available */ + if (commonstate == NULL || commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read the result for the running query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3994,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4083,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4113,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4128,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4167,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4177,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4190,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4321,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4489,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4499,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5993,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.2 ----Next_Part(Fri_Feb_28_17_06_50_2020_928)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v7 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 10e23d02ed..0634ab9f6a 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6986,7 +6986,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7014,7 +7014,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7042,7 +7042,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7070,7 +7070,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7140,35 +7140,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7178,35 +7184,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7236,11 +7248,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7254,12 +7267,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7289,16 +7303,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7316,17 +7331,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7476,27 +7492,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8571,11 +8593,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8610,20 +8633,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8652,11 +8677,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8709,21 +8735,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8758,18 +8786,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8780,13 +8809,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8808,29 +8838,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8850,20 +8873,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index a31abce7c9..14824368cc 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1433,12 +1475,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1486,40 +1538,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1534,7 +1787,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1542,6 +1795,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1570,9 +1825,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1590,7 +1845,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1598,15 +1853,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2371,7 +2642,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2456,7 +2729,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2503,8 +2780,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2702,6 +2979,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2746,6 +3024,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3316,11 +3606,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3383,50 +3673,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3436,22 +3795,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3565,7 +3975,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3652,6 +4064,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3679,14 +4094,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3694,10 +4109,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3733,7 +4148,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3743,12 +4158,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3756,9 +4171,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3887,16 +4302,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4055,9 +4470,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4065,10 +4480,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5559,6 +5974,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 78156d10b4..17d461b1a4 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1799,25 +1799,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1859,12 +1859,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1923,8 +1923,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Oct__1_13_43_31_2020_721)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v3 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 222 ++++--- contrib/postgres_fdw/postgres_fdw.c | 603 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 694 insertions(+), 181 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..29aa09db8e 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..b04b6a0e54 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,244 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + /* It's the leader */ + ForeignScanState *next_leader; + + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1791,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1799,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1829,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1849,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1857,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2646,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2733,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2784,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2983,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3028,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3610,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3677,120 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; char sql[64]; - int numrows; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3800,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3980,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4069,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4099,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4114,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4153,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4163,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4176,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4307,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4475,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4485,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5979,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.2 ----Next_Part(Thu_Jun__4_15_00_15_2020_826)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v4 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 222 ++++--- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 691 insertions(+), 182 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..29aa09db8e 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.2 ----Next_Part(Wed_Jun_10_12_05_10_2020_221)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v5 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 52d1fe3563..d9edc5e4de 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -58,6 +58,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 82fc1290ef..bf9b4041cd 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Jul__2_11_14_48_2020_705)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* [PATCH v6 3/3] async postgres_fdw @ 2017-10-19 08:24 Kyotaro Horiguchi <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: Kyotaro Horiguchi @ 2017-10-19 08:24 UTC (permalink / raw) --- contrib/postgres_fdw/connection.c | 28 + .../postgres_fdw/expected/postgres_fdw.out | 272 ++++---- contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++--- contrib/postgres_fdw/postgres_fdw.h | 2 + contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +- 5 files changed, 710 insertions(+), 213 deletions(-) diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 08daf26fdf..be5948f613 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -59,6 +59,7 @@ typedef struct ConnCacheEntry bool invalidated; /* true if reconnect is pending */ uint32 server_hashvalue; /* hash value of foreign server OID */ uint32 mapping_hashvalue; /* hash value of user mapping OID */ + void *storage; /* connection specific storage */ } ConnCacheEntry; /* @@ -203,6 +204,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt) elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)", entry->conn, server->servername, user->umid, user->userid); + entry->storage = NULL; } /* @@ -216,6 +218,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt) return entry->conn; } +/* + * Returns the connection specific storage for this user. Allocate with + * initsize if not exists. + */ +void * +GetConnectionSpecificStorage(UserMapping *user, size_t initsize) +{ + bool found; + ConnCacheEntry *entry; + ConnCacheKey key; + + /* Find storage using the same key with GetConnection */ + key = user->umid; + entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found); + Assert(found); + + /* Create one if not yet. */ + if (entry->storage == NULL) + { + entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize); + memset(entry->storage, 0, initsize); + } + + return entry->storage; +} + /* * Connect to remote server using specified server and user mapping properties. */ diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 90db550b92..9374fa3a6c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa'); INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+------- a | aaa @@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | aaa @@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a; (3 rows) UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; tableoid | aa ----------+-------- a | newtoo @@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33); insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for update; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; f1 | f2 ----+---- 1 | 11 @@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update; (4 rows) explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; - QUERY PLAN ----------------------------------------------------------------------------------------------- +select * from bar where f1 in (select f1 from foo) order by 1 for share; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- LockRows Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid - -> Hash Join + -> Merge Join Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid Inner Unique: true - Hash Cond: (bar.f1 = foo.f1) - -> Append - -> Seq Scan on public.bar bar_1 + Merge Cond: (bar.f1 = foo.f1) + -> Merge Append + Sort Key: bar.f1 + -> Sort Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid + Sort Key: bar_1.f1 + -> Seq Scan on public.bar bar_1 + Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid -> Foreign Scan on public.bar2 bar_2 Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid - Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE - -> Hash + Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE + -> Sort Output: foo.ctid, foo.f1, foo.*, foo.tableoid + Sort Key: foo.f1 -> HashAggregate Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(23 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(29 rows) -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; f1 | f2 ----+---- 1 | 11 @@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid -> Hash Join Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid Inner Unique: true @@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo); Output: foo.ctid, foo.f1, foo.*, foo.tableoid Group Key: foo.f1 -> Append - -> Seq Scan on public.foo foo_1 - Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid - -> Foreign Scan on public.foo2 foo_2 + Async subplans: 1 + -> Async Foreign Scan on public.foo2 foo_2 Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1 -(39 rows) + -> Seq Scan on public.foo foo_1 + Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid +(41 rows) update bar set f2 = f2 + 100 where f1 in (select f1 from foo); select tableoid::regclass, * from bar order by 1,2; @@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1; Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1)) Hash Cond: (foo.f1 = bar.f1) -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -> Hash Output: bar.f1, bar.f2, bar.ctid -> Seq Scan on public.bar @@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1; Output: (ROW(foo.f1)), foo.f1 Sort Key: foo.f1 -> Append + Async subplans: 2 + -> Async Foreign Scan on public.foo2 foo_1 + Output: ROW(foo_1.f1), foo_1.f1 + Remote SQL: SELECT f1 FROM public.loct1 + -> Async Foreign Scan on public.foo2 foo_3 + Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) + Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo Output: ROW(foo.f1), foo.f1 - -> Foreign Scan on public.foo2 foo_1 - Output: ROW(foo_1.f1), foo_1.f1 - Remote SQL: SELECT f1 FROM public.loct1 -> Seq Scan on public.foo foo_2 Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3) - -> Foreign Scan on public.foo2 foo_3 - Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3) - Remote SQL: SELECT f1 FROM public.loct1 -(45 rows) +(47 rows) update bar set f2 = f2 + 100 from @@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *; (5 rows) explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; - QUERY PLAN ------------------------------------------------------------------------------- - Update on public.bar - Output: bar.f1, bar.f2 - Update on public.bar - Foreign Update on public.bar2 bar_1 - -> Seq Scan on public.bar - Output: bar.f1, (bar.f2 + 100), bar.ctid - -> Foreign Update on public.bar2 bar_1 - Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 -(8 rows) +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; + QUERY PLAN +-------------------------------------------------------------------------------------- + Sort + Output: u.f1, u.f2 + Sort Key: u.f1 + CTE u + -> Update on public.bar + Output: bar.f1, bar.f2 + Update on public.bar + Foreign Update on public.bar2 bar_1 + -> Seq Scan on public.bar + Output: bar.f1, (bar.f2 + 100), bar.ctid + -> Foreign Update on public.bar2 bar_1 + Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2 + -> CTE Scan on u + Output: u.f1, u.f2 +(14 rows) -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; f1 | f2 ----+----- 1 | 311 2 | 322 - 6 | 266 3 | 333 4 | 344 + 6 | 266 7 | 277 (6 rows) @@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J Sort Sort Key: t1.a, t3.c -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1) - -> Foreign Scan + -> Async Foreign Scan Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2) -(7 rows) +(8 rows) SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE t1.a % 25 =0 ORDER BY 1,2,3; a | b | c @@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) -- with whole-row reference; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; - QUERY PLAN --------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------- Sort Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2) -> Hash Full Join Hash Cond: (t1.a = t2.b) -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 -> Hash -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 -(11 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 +(13 rows) SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2 t2 WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2; wr | wr @@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t Sort Sort Key: t1.a, t1.b -> Append - -> Foreign Scan + Async subplans: 2 + -> Async Foreign Scan Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1) - -> Foreign Scan + -> Async Foreign Scan Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2) -(7 rows) +(8 rows) SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE t1.a%25 = 0 ORDER BY 1,2; a | b @@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE -- test FOR UPDATE; partitionwise join does not apply EXPLAIN (COSTS OFF) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; - QUERY PLAN --------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------- LockRows -> Sort Sort Key: t1.a -> Hash Join Hash Cond: (t2.b = t1.a) -> Append - -> Foreign Scan on ftprt2_p1 t2_1 - -> Foreign Scan on ftprt2_p2 t2_2 + Async subplans: 2 + -> Async Foreign Scan on ftprt2_p1 t2_1 + -> Async Foreign Scan on ftprt2_p2 t2_2 -> Hash -> Append - -> Foreign Scan on ftprt1_p1 t1_1 - -> Foreign Scan on ftprt1_p2 t1_2 -(12 rows) + Async subplans: 2 + -> Async Foreign Scan on ftprt1_p1 t1_1 + -> Async Foreign Scan on ftprt1_p2 t1_2 +(14 rows) SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF t1; a | b @@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3; SET enable_partitionwise_aggregate TO false; EXPLAIN (COSTS OFF) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; - QUERY PLAN ------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------- Sort Sort Key: pagg_tab.a -> HashAggregate Group Key: pagg_tab.a Filter: (avg(pagg_tab.b) < '22'::numeric) -> Append - -> Foreign Scan on fpagg_tab_p1 pagg_tab_1 - -> Foreign Scan on fpagg_tab_p2 pagg_tab_2 - -> Foreign Scan on fpagg_tab_p3 pagg_tab_3 -(9 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- Plan with partitionwise aggregates is enabled SET enable_partitionwise_aggregate TO true; @@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O Sort Sort Key: pagg_tab.a -> Append - -> Foreign Scan + Async subplans: 3 + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p1 pagg_tab) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1) - -> Foreign Scan + -> Async Foreign Scan Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2) -(9 rows) +(10 rows) SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | sum | min | count @@ -8795,29 +8825,22 @@ SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; Sort Output: t1.a, (count(((t1.*)::pagg_tab))) Sort Key: t1.a - -> Append - -> HashAggregate - Output: t1.a, count(((t1.*)::pagg_tab)) - Group Key: t1.a - Filter: (avg(t1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p1 t1 - Output: t1.a, t1.*, t1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 - -> HashAggregate - Output: t1_1.a, count(((t1_1.*)::pagg_tab)) - Group Key: t1_1.a - Filter: (avg(t1_1.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p2 t1_1 + -> HashAggregate + Output: t1.a, count(((t1.*)::pagg_tab)) + Group Key: t1.a + Filter: (avg(t1.b) < '22'::numeric) + -> Append + Async subplans: 3 + -> Async Foreign Scan on public.fpagg_tab_p1 t1_1 Output: t1_1.a, t1_1.*, t1_1.b - Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 - -> HashAggregate - Output: t1_2.a, count(((t1_2.*)::pagg_tab)) - Group Key: t1_2.a - Filter: (avg(t1_2.b) < '22'::numeric) - -> Foreign Scan on public.fpagg_tab_p3 t1_2 + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p1 + -> Async Foreign Scan on public.fpagg_tab_p2 t1_2 Output: t1_2.a, t1_2.*, t1_2.b + Remote SQL: SELECT a, b, c FROM public.pagg_tab_p2 + -> Async Foreign Scan on public.fpagg_tab_p3 t1_3 + Output: t1_3.a, t1_3.*, t1_3.b Remote SQL: SELECT a, b, c FROM public.pagg_tab_p3 -(25 rows) +(18 rows) SELECT a, count(t1) FROM pagg_tab t1 GROUP BY a HAVING avg(b) < 22 ORDER BY 1; a | count @@ -8837,20 +8860,15 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ----------------------------------------------------------------- Sort Sort Key: pagg_tab.b - -> Finalize HashAggregate + -> HashAggregate Group Key: pagg_tab.b Filter: (sum(pagg_tab.a) < 700) -> Append - -> Partial HashAggregate - Group Key: pagg_tab.b - -> Foreign Scan on fpagg_tab_p1 pagg_tab - -> Partial HashAggregate - Group Key: pagg_tab_1.b - -> Foreign Scan on fpagg_tab_p2 pagg_tab_1 - -> Partial HashAggregate - Group Key: pagg_tab_2.b - -> Foreign Scan on fpagg_tab_p3 pagg_tab_2 -(15 rows) + Async subplans: 3 + -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1 + -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2 + -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3 +(10 rows) -- =================================================================== -- access rights and superuser diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..4bfc2d39ea 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -21,6 +21,8 @@ #include "commands/defrem.h" #include "commands/explain.h" #include "commands/vacuum.h" +#include "executor/execAsync.h" +#include "executor/nodeForeignscan.h" #include "foreign/fdwapi.h" #include "funcapi.h" #include "miscadmin.h" @@ -35,6 +37,7 @@ #include "optimizer/restrictinfo.h" #include "optimizer/tlist.h" #include "parser/parsetree.h" +#include "pgstat.h" #include "postgres_fdw.h" #include "utils/builtins.h" #include "utils/float.h" @@ -56,6 +59,9 @@ PG_MODULE_MAGIC; /* If no remote estimates, assume a sort costs 20% extra */ #define DEFAULT_FDW_SORT_MULTIPLIER 1.2 +/* Retrieve PgFdwScanState struct from ForeignScanState */ +#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state) + /* * Indexes of FDW-private information stored in fdw_private lists. * @@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex FdwDirectModifyPrivateSetProcessed }; +/* + * Connection common state - shared among all PgFdwState instances using the + * same connection. + */ +typedef struct PgFdwConnCommonState +{ + ForeignScanState *leader; /* leader node of this connection */ + bool busy; /* true if this connection is busy */ +} PgFdwConnCommonState; + +/* Execution state base type */ +typedef struct PgFdwState +{ + PGconn *conn; /* connection for the scan */ + PgFdwConnCommonState *commonstate; /* connection common state */ +} PgFdwState; + /* * Execution state of a foreign scan using postgres_fdw. */ typedef struct PgFdwScanState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table. NULL * for a foreign join scan. */ TupleDesc tupdesc; /* tuple descriptor of scan */ @@ -137,7 +161,6 @@ typedef struct PgFdwScanState List *retrieved_attrs; /* list of retrieved attribute numbers */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ unsigned int cursor_number; /* quasi-unique ID for my cursor */ bool cursor_exists; /* have we created the cursor? */ int numParams; /* number of parameters passed to query */ @@ -153,6 +176,12 @@ typedef struct PgFdwScanState /* batch-level state, for optimizing rewinds and avoiding useless fetch */ int fetch_ct_2; /* Min(# of fetches done, 2) */ bool eof_reached; /* true if last fetch reached EOF */ + bool async; /* true if run asynchronously */ + bool queued; /* true if this node is in waiter queue */ + ForeignScanState *waiter; /* Next node to run a query among nodes + * sharing the same connection */ + ForeignScanState *last_waiter; /* last element in waiter queue. + * valid only on the leader node */ /* working memory contexts */ MemoryContext batch_cxt; /* context holding current batch of tuples */ @@ -166,11 +195,11 @@ typedef struct PgFdwScanState */ typedef struct PgFdwModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ /* for remote query execution */ - PGconn *conn; /* connection for the scan */ char *p_name; /* name of prepared statement, if created */ /* extracted fdw_private data */ @@ -197,6 +226,7 @@ typedef struct PgFdwModifyState */ typedef struct PgFdwDirectModifyState { + PgFdwState s; /* common structure */ Relation rel; /* relcache entry for the foreign table */ AttInMetadata *attinmeta; /* attribute datatype conversion metadata */ @@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags); static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node); static void postgresReScanForeignScan(ForeignScanState *node); static void postgresEndForeignScan(ForeignScanState *node); +static void postgresShutdownForeignScan(ForeignScanState *node); static void postgresAddForeignUpdateTargets(Query *parsetree, RangeTblEntry *target_rte, Relation target_relation); @@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root, RelOptInfo *input_rel, RelOptInfo *output_rel, void *extra); +static bool postgresIsForeignPathAsyncCapable(ForeignPath *path); +static bool postgresForeignAsyncConfigureWait(ForeignScanState *node, + WaitEventSet *wes, + void *caller_data, bool reinit); /* * Helper functions @@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); static void create_cursor(ForeignScanState *node); -static void fetch_more_data(ForeignScanState *node); +static void request_more_data(ForeignScanState *node); +static void fetch_received_data(ForeignScanState *node); +static void vacate_connection(PgFdwState *fdwconn, bool clear_queue); static void close_cursor(PGconn *conn, unsigned int cursor_number); static PgFdwModifyState *create_foreign_modify(EState *estate, RangeTblEntry *rte, @@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) routine->IterateForeignScan = postgresIterateForeignScan; routine->ReScanForeignScan = postgresReScanForeignScan; routine->EndForeignScan = postgresEndForeignScan; + routine->ShutdownForeignScan = postgresShutdownForeignScan; /* Functions for updating foreign tables */ routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets; @@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) /* Support functions for upper relation push-down */ routine->GetForeignUpperPaths = postgresGetForeignUpperPaths; + /* Support functions for async execution */ + routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable; + routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait; + PG_RETURN_POINTER(routine); } @@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - fsstate->conn = GetConnection(user, false); + fsstate->s.conn = GetConnection(user, false); + fsstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); + fsstate->s.commonstate->leader = NULL; + fsstate->s.commonstate->busy = false; + fsstate->waiter = NULL; + fsstate->last_waiter = node; /* Assign a unique ID for my cursor */ - fsstate->cursor_number = GetCursorNumber(fsstate->conn); + fsstate->cursor_number = GetCursorNumber(fsstate->s.conn); fsstate->cursor_exists = false; + /* Initialize async execution status */ + fsstate->async = false; + fsstate->queued = false; + /* Get private info created by planner functions. */ fsstate->query = strVal(list_nth(fsplan->fdw_private, FdwScanPrivateSelectSql)); @@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) &fsstate->param_values); } +/* + * Async queue manipulation functions + */ + +/* + * add_async_waiter: + * + * Enqueue node if it isn't in the queue. Immediately send request it if the + * underlying connection is not busy. + */ +static inline void +add_async_waiter(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + + /* + * Do nothing if the node is already in the queue or already eof'ed. + * Note: leader node is not marked as queued. + */ + if (leader == node || fsstate->queued || fsstate->eof_reached) + return; + + if (leader == NULL) + { + /* no leader means not busy, send request immediately */ + request_more_data(node); + } + else + { + /* the connection is busy, queue the node */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PgFdwScanState *last_waiter_state + = GetPgFdwScanState(leader_state->last_waiter); + + last_waiter_state->waiter = node; + leader_state->last_waiter = node; + fsstate->queued = true; + } +} + +/* + * move_to_next_waiter: + * + * Make the first waiter be the next leader + * Returns the new leader or NULL if there's no waiter. + */ +static inline ForeignScanState * +move_to_next_waiter(ForeignScanState *node) +{ + PgFdwScanState *leader_state = GetPgFdwScanState(node); + ForeignScanState *next_leader = leader_state->waiter; + + Assert(leader_state->s.commonstate->leader = node); + + if (next_leader) + { + /* the first waiter becomes the next leader */ + PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader); + next_leader_state->last_waiter = leader_state->last_waiter; + next_leader_state->queued = false; + } + + leader_state->waiter = NULL; + leader_state->s.commonstate->leader = next_leader; + + return next_leader; +} + +/* + * Remove the node from waiter queue. + * + * Remaining results are cleared if the node is a busy leader. + * This intended to be used during node shutdown. + */ +static inline void +remove_async_node(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state; + ForeignScanState *prev; + PgFdwScanState *prev_state; + ForeignScanState *cur; + + /* no need to remove me */ + if (!leader || !fsstate->queued) + return; + + leader_state = GetPgFdwScanState(leader); + + if (leader == node) + { + if (leader_state->s.commonstate->busy) + { + /* + * this node is waiting for result, absorb the result first so + * that the following commands can be sent on the connection. + */ + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + PGconn *conn = leader_state->s.conn; + + while(PQisBusy(conn)) + PQclear(PQgetResult(conn)); + + leader_state->s.commonstate->busy = false; + } + + move_to_next_waiter(node); + + return; + } + + /* + * Just remove the node from the queue + * + * Nodes don't have a link to the previous node but anyway this function is + * called on the shutdown path, so we don't bother seeking for faster way + * to do this. + */ + prev = leader; + prev_state = leader_state; + cur = GetPgFdwScanState(prev)->waiter; + while (cur) + { + PgFdwScanState *curstate = GetPgFdwScanState(cur); + + if (cur == node) + { + prev_state->waiter = curstate->waiter; + + /* relink to the previous node if the last node was removed */ + if (leader_state->last_waiter == cur) + leader_state->last_waiter = prev; + + fsstate->queued = false; + + return; + } + prev = cur; + prev_state = curstate; + cur = curstate->waiter; + } +} + /* * postgresIterateForeignScan - * Retrieve next row from the result set, or clear tuple slot to indicate - * EOF. + * Retrieve next row from the result set. + * + * For synchronous nodes, returns clear tuple slot means EOF. + * + * For asynchronous nodes, if clear tuple slot is returned, the caller + * needs to check async state to tell if all tuples received + * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING). */ static TupleTableSlot * postgresIterateForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); TupleTableSlot *slot = node->ss.ss_ScanTupleSlot; - /* - * If this is the first call after Begin or ReScan, we need to create the - * cursor on the remote side. - */ - if (!fsstate->cursor_exists) - create_cursor(node); - - /* - * Get some more tuples, if we've run out. - */ + if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached) + { + /* we've run out, get some more tuples */ + if (!node->fs_async) + { + /* + * finish the running query before sending the next command for + * this node + */ + if (!fsstate->s.commonstate->busy) + vacate_connection((PgFdwState *)fsstate, false); + + request_more_data(node); + + /* Fetch the result immediately. */ + fetch_received_data(node); + } + else if (!fsstate->s.commonstate->busy) + { + /* If the connection is not busy, just send the request. */ + request_more_data(node); + } + else + { + /* The connection is busy, queue the request */ + bool available = true; + ForeignScanState *leader = fsstate->s.commonstate->leader; + PgFdwScanState *leader_state = GetPgFdwScanState(leader); + + /* queue the requested node */ + add_async_waiter(node); + + /* + * The request for the next node cannot be sent before the leader + * responds. Finish the current leader if possible. + */ + if (PQisBusy(leader_state->s.conn)) + { + int rc = WaitLatchOrSocket(NULL, + WL_SOCKET_READABLE | WL_TIMEOUT | + WL_EXIT_ON_PM_DEATH, + PQsocket(leader_state->s.conn), 0, + WAIT_EVENT_ASYNC_WAIT); + if (!(rc & WL_SOCKET_READABLE)) + available = false; + } + + /* fetch the leader's data and enqueue it for the next request */ + if (available) + { + fetch_received_data(leader); + add_async_waiter(leader); + } + } + } + if (fsstate->next_tuple >= fsstate->num_tuples) { - /* No point in another fetch if we already detected EOF, though. */ - if (!fsstate->eof_reached) - fetch_more_data(node); - /* If we didn't get any tuples, must be end of data. */ - if (fsstate->next_tuple >= fsstate->num_tuples) - return ExecClearTuple(slot); + /* + * We haven't received a result for the given node this time, return + * with no tuple to give way to another node. + */ + if (fsstate->eof_reached) + node->ss.ps.asyncstate = AS_AVAILABLE; + else + node->ss.ps.asyncstate = AS_WAITING; + + return ExecClearTuple(slot); } /* * Return the next tuple. */ + node->ss.ps.asyncstate = AS_AVAILABLE; ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++], slot, false); @@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node) static void postgresReScanForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); char sql[64]; PGresult *res; @@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node) if (!fsstate->cursor_exists) return; + vacate_connection((PgFdwState *)fsstate, true); + /* * If any internal parameters affecting this node have changed, we'd * better destroy and recreate the cursor. Otherwise, rewinding it should @@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fsstate->conn, sql); + res = pgfdw_exec_query(fsstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node) static void postgresEndForeignScan(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); /* if fsstate is NULL, we are in EXPLAIN; nothing to do */ if (fsstate == NULL) @@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node) /* Close the cursor if open, to prevent accumulation of cursors */ if (fsstate->cursor_exists) - close_cursor(fsstate->conn, fsstate->cursor_number); + close_cursor(fsstate->s.conn, fsstate->cursor_number); /* Release remote connection */ - ReleaseConnection(fsstate->conn); - fsstate->conn = NULL; + ReleaseConnection(fsstate->s.conn); + fsstate->s.conn = NULL; /* MemoryContexts will be deleted automatically. */ } +/* + * postgresShutdownForeignScan + * Remove asynchrony stuff and cleanup garbage on the connection. + */ +static void +postgresShutdownForeignScan(ForeignScanState *node) +{ + ForeignScan *plan = (ForeignScan *) node->ss.ps.plan; + + if (plan->operation != CMD_SELECT) + return; + + /* remove the node from waiting queue */ + remove_async_node(node); +} + /* * postgresAddForeignUpdateTargets * Add resjunk column(s) needed for update/delete on a foreign table @@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) * Get connection to the foreign server. Connection manager will * establish new connection if necessary. */ - dmstate->conn = GetConnection(user, false); + dmstate->s.conn = GetConnection(user, false); + dmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); /* Update the foreign-join-related fields. */ if (fsplan->scan.scanrelid == 0) @@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node) * If this is the first call after Begin, execute the statement. */ if (dmstate->num_tuples == -1) + { + /* finish running query to send my command */ + vacate_connection((PgFdwState *)dmstate, true); execute_dml_stmt(node); + } /* * If the local query doesn't specify RETURNING, just clear tuple slot. @@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node) PQclear(dmstate->result); /* Release remote connection */ - ReleaseConnection(dmstate->conn); - dmstate->conn = NULL; + ReleaseConnection(dmstate->s.conn); + dmstate->s.conn = NULL; /* MemoryContext will be deleted automatically. */ } @@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root, List *local_param_join_conds; StringInfoData sql; PGconn *conn; + PgFdwConnCommonState *commonstate; Selectivity local_sel; QualCost local_cost; List *fdw_scan_tlist = NIL; @@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root, /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); + commonstate = GetConnectionSpecificStorage(fpinfo->user, + sizeof(PgFdwConnCommonState)); + if (commonstate) + { + PgFdwState tmpstate; + tmpstate.conn = conn; + tmpstate.commonstate = commonstate; + + /* finish running query to send my command */ + vacate_connection(&tmpstate, true); + } + get_remote_estimate(sql.data, conn, &rows, &width, &startup_cost, &total_cost); ReleaseConnection(conn); @@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel, static void create_cursor(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); ExprContext *econtext = node->ss.ps.ps_ExprContext; int numParams = fsstate->numParams; const char **values = fsstate->param_values; - PGconn *conn = fsstate->conn; + PGconn *conn = fsstate->s.conn; StringInfoData buf; PGresult *res; @@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node) } /* - * Fetch some more rows from the node's cursor. + * Sends the next request of the node. If the given node is different from the + * current connection leader, pushes it back to waiter queue and let the given + * node be the leader. */ static void -fetch_more_data(ForeignScanState *node) +request_more_data(ForeignScanState *node) { - PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; + PgFdwScanState *fsstate = GetPgFdwScanState(node); + ForeignScanState *leader = fsstate->s.commonstate->leader; + PGconn *conn = fsstate->s.conn; + char sql[64]; + + /* must be non-busy */ + Assert(!fsstate->s.commonstate->busy); + /* must be not-eof'ed */ + Assert(!fsstate->eof_reached); + + /* + * If this is the first call after Begin or ReScan, we need to create the + * cursor on the remote side. + */ + if (!fsstate->cursor_exists) + create_cursor(node); + + snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", + fsstate->fetch_size, fsstate->cursor_number); + + if (!PQsendQuery(conn, sql)) + pgfdw_report_error(ERROR, NULL, conn, false, sql); + + fsstate->s.commonstate->busy = true; + + /* The node is the current leader, just return. */ + if (leader == node) + return; + + /* Let the node be the leader */ + if (leader != NULL) + { + remove_async_node(node); + fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter; + fsstate->waiter = leader; + } + else + { + fsstate->last_waiter = node; + fsstate->waiter = NULL; + } + + fsstate->s.commonstate->leader = node; +} + +/* + * Fetches received data and automatically send requests of the next waiter. + */ +static void +fetch_received_data(ForeignScanState *node) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); PGresult *volatile res = NULL; MemoryContext oldcontext; + ForeignScanState *waiter; + + /* I should be the current connection leader */ + Assert(fsstate->s.commonstate->leader == node); /* * We'll store the tuples in the batch_cxt. First, flush the previous - * batch. + * batch if no tuple is remaining */ - fsstate->tuples = NULL; - MemoryContextReset(fsstate->batch_cxt); + if (fsstate->next_tuple >= fsstate->num_tuples) + { + fsstate->tuples = NULL; + fsstate->num_tuples = 0; + MemoryContextReset(fsstate->batch_cxt); + } + else if (fsstate->next_tuple > 0) + { + /* There's some remains. Move them to the beginning of the store */ + int n = 0; + + while(fsstate->next_tuple < fsstate->num_tuples) + fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++]; + fsstate->num_tuples = n; + } + oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); /* PGresult must be released before leaving this function. */ PG_TRY(); { - PGconn *conn = fsstate->conn; - char sql[64]; - int numrows; + PGconn *conn = fsstate->s.conn; + int addrows; + size_t newsize; int i; - snprintf(sql, sizeof(sql), "FETCH %d FROM c%u", - fsstate->fetch_size, fsstate->cursor_number); - - res = pgfdw_exec_query(conn, sql); - /* On error, report the original query, not the FETCH. */ + res = pgfdw_get_result(conn, fsstate->query); if (PQresultStatus(res) != PGRES_TUPLES_OK) pgfdw_report_error(ERROR, res, conn, false, fsstate->query); /* Convert the data into HeapTuples */ - numrows = PQntuples(res); - fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple)); - fsstate->num_tuples = numrows; - fsstate->next_tuple = 0; + addrows = PQntuples(res); + newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple); + if (fsstate->tuples) + fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize); + else + fsstate->tuples = (HeapTuple *) palloc(newsize); - for (i = 0; i < numrows; i++) + for (i = 0; i < addrows; i++) { Assert(IsA(node->ss.ps.plan, ForeignScan)); - fsstate->tuples[i] = + fsstate->tuples[fsstate->num_tuples + i] = make_tuple_from_result_row(res, i, fsstate->rel, fsstate->attinmeta, @@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node) } /* Update fetch_ct_2 */ - if (fsstate->fetch_ct_2 < 2) + if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0) fsstate->fetch_ct_2++; + fsstate->next_tuple = 0; + fsstate->num_tuples += addrows; + /* Must be EOF if we didn't get as many tuples as we asked for. */ - fsstate->eof_reached = (numrows < fsstate->fetch_size); + fsstate->eof_reached = (addrows < fsstate->fetch_size); } PG_FINALLY(); { + fsstate->s.commonstate->busy = false; + if (res) PQclear(res); } PG_END_TRY(); + /* let the first waiter be the next leader of this connection */ + waiter = move_to_next_waiter(node); + + /* send the next request if any */ + if (waiter) + request_more_data(waiter); + MemoryContextSwitchTo(oldcontext); } +/* + * Vacate the underlying connection so that this node can send the next query. + */ +static void +vacate_connection(PgFdwState *fdwstate, bool clear_queue) +{ + PgFdwConnCommonState *commonstate = fdwstate->commonstate; + ForeignScanState *leader; + + Assert(commonstate != NULL); + + /* just return if the connection is already available */ + if (commonstate->leader == NULL || !commonstate->busy) + return; + + /* + * let the current connection leader read all of the result for the running + * query + */ + leader = commonstate->leader; + fetch_received_data(leader); + + /* let the first waiter be the next leader of this connection */ + move_to_next_waiter(leader); + + if (!clear_queue) + return; + + /* Clear the waiting list */ + while (leader) + { + PgFdwScanState *fsstate = GetPgFdwScanState(leader); + + fsstate->last_waiter = NULL; + leader = fsstate->waiter; + fsstate->waiter = NULL; + } +} + /* * Force assorted GUC parameters to settings that ensure that we'll output * data values in a form that is unambiguous to the remote server. @@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate, user = GetUserMapping(userid, table->serverid); /* Open connection; report that we'll create a prepared statement. */ - fmstate->conn = GetConnection(user, true); + fmstate->s.conn = GetConnection(user, true); + fmstate->s.commonstate = (PgFdwConnCommonState *) + GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState)); fmstate->p_name = NULL; /* prepared statement not made yet */ /* Set up remote query information. */ @@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate, operation == CMD_UPDATE || operation == CMD_DELETE); + /* finish running query to send my command */ + vacate_connection((PgFdwState *)fmstate, true); + /* Set up the prepared statement on the remote server, if we didn't yet */ if (!fmstate->p_name) prepare_foreign_modify(fmstate); @@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate, /* * Execute the prepared statement. */ - if (!PQsendQueryPrepared(fmstate->conn, + if (!PQsendQueryPrepared(fmstate->s.conn, fmstate->p_name, fmstate->p_nums, p_values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate, * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) /* Construct name we'll use for the prepared statement. */ snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u", - GetPrepStmtNumber(fmstate->conn)); + GetPrepStmtNumber(fmstate->s.conn)); p_name = pstrdup(prep_name); /* @@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * the prepared statements we use in this module are simple enough that * the remote server will make the right choices. */ - if (!PQsendPrepare(fmstate->conn, + if (!PQsendPrepare(fmstate->s.conn, p_name, fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query); /* * Get the result, and check for success. @@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_get_result(fmstate->conn, fmstate->query); + res = pgfdw_get_result(fmstate->s.conn, fmstate->query); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - res = pgfdw_exec_query(fmstate->conn, sql); + res = pgfdw_exec_query(fmstate->s.conn, sql); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql); PQclear(res); fmstate->p_name = NULL; } /* Release remote connection */ - ReleaseConnection(fmstate->conn); - fmstate->conn = NULL; + ReleaseConnection(fmstate->s.conn); + fmstate->s.conn = NULL; } /* @@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node) * the desired result. This allows us to avoid assuming that the remote * server has the same OIDs we do for the parameters' types. */ - if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, + if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query); /* * Get the result, and check for success. @@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node) * We don't use a PG_TRY block here, so be careful not to throw error * without releasing the PGresult. */ - dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query); + dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true, dmstate->query); /* Get the number of rows affected. */ @@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root, /* XXX Consider parameterized paths for the join relation */ } +static bool +postgresIsForeignPathAsyncCapable(ForeignPath *path) +{ + return true; +} + + +/* + * Configure waiting event. + * + * Add wait event so that the ForeignScan node is going to wait for. + */ +static bool +postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes, + void *caller_data, bool reinit) +{ + PgFdwScanState *fsstate = GetPgFdwScanState(node); + + + /* Reinit is not supported for now. */ + Assert(reinit); + + if (fsstate->s.commonstate->leader == node) + { + AddWaitEventToSet(wes, + WL_SOCKET_READABLE, PQsocket(fsstate->s.conn), + NULL, caller_data); + return true; + } + + return false; +} + + /* * Assess whether the aggregation, grouping and having operations can be pushed * down to the foreign server. As a side effect, save information we obtain in diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index eef410db39..96af75a33e 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo UserMapping *user; /* only set in use_remote_estimate mode */ int fetch_size; /* fetch size for this remote table */ + bool allow_prefetch; /* true to allow overlapped fetching */ /* * Name of the relation, for use while EXPLAINing ForeignScan. It is used @@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel); /* in connection.c */ extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 83971665e3..359208a12a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb'); INSERT INTO b(aa) VALUES('bbbb'); INSERT INTO b(aa) VALUES('bbbbb'); -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE b SET aa = 'new'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; UPDATE a SET aa = 'newtoo'; -SELECT tableoid::regclass, * FROM a; +SELECT tableoid::regclass, * FROM a ORDER BY 1, 2; SELECT tableoid::regclass, * FROM b; SELECT tableoid::regclass, * FROM ONLY a; @@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44); insert into bar2 values(7,77,77); explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for update; -select * from bar where f1 in (select f1 from foo) for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; +select * from bar where f1 in (select f1 from foo) order by 1 for update; explain (verbose, costs off) -select * from bar where f1 in (select f1 from foo) for share; -select * from bar where f1 in (select f1 from foo) for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; +select * from bar where f1 in (select f1 from foo) order by 1 for share; -- Check UPDATE with inherited target and an inherited source table explain (verbose, costs off) @@ -1904,8 +1904,8 @@ explain (verbose, costs off) delete from foo where f1 < 5 returning *; delete from foo where f1 < 5 returning *; explain (verbose, costs off) -update bar set f2 = f2 + 100 returning *; -update bar set f2 = f2 + 100 returning *; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; +with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1; -- Test that UPDATE/DELETE with inherited target works with row-level triggers CREATE TRIGGER trig_row_before -- 2.18.4 ----Next_Part(Thu_Aug_20_16_36_08_2020_519)---- ^ permalink raw reply [nested|flat] 60+ messages in thread
* support virtual generated column not null constraint @ 2025-02-10 13:33 jian he <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: jian he @ 2025-02-10 13:33 UTC (permalink / raw) To: pgsql-hackers hi. Virtual generated columns committed, https://git.postgresql.org/cgit/postgresql.git/commit/?id=83ea6c54025bea67bcd4949a6d58d3fc11c3e21b This patch is for implementing not null constraints on virtual generated columns. NOT NULL constraints on virtual generated columns mean that if we INSERT a row into the table and the evaluation of the generated expression results in a null value, an ERRCODE_NOT_NULL_VIOLATION error will be reported. main gotcha is in ExecConstraints, expand the generated expression and convert a not null constraint to a check constraint and evaluate it. Attachments: [text/x-patch] v1-0001-support-virtual-generated-column-not-null-constra.patch (16.4K, ../../CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com/2-v1-0001-support-virtual-generated-column-not-null-constra.patch) download | inline diff: From 945ee799beca62e76f128660aef658ef61a11a8a Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Mon, 10 Feb 2025 21:20:02 +0800 Subject: [PATCH v1 1/1] support virtual generated column not null constraint now we can add not null constraint on virtual generated column. not null constraint on virtual generated column make sure evaulation of the expanded generated expression does not yield null. discussion: https://postgr.es/m/ --- src/backend/catalog/heap.c | 10 -- src/backend/commands/tablecmds.c | 8 - src/backend/executor/execMain.c | 152 ++++++++++++++++++ src/backend/parser/parse_utilcmd.c | 14 -- src/include/nodes/execnodes.h | 2 + .../regress/expected/generated_virtual.out | 27 ++-- src/test/regress/sql/generated_virtual.sql | 12 +- 7 files changed, 172 insertions(+), 53 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index 956f196fc9..2d42761c91 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -2564,11 +2564,6 @@ AddRelationNewConstraints(Relation rel, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(cdef->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), colnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * If the column already has a not-null constraint, we don't want @@ -2884,11 +2879,6 @@ AddRelationNotNullConstraints(Relation rel, List *constraints, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(constr->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), attnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * A column can only have one not-null constraint, so discard any diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 5823fce934..d672d1b060 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -7803,14 +7803,6 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName, errmsg("cannot alter system column \"%s\"", colName))); - /* TODO: see transformColumnDefinition() */ - if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", - colName, RelationGetRelationName(rel)))); - /* See if there's already a constraint */ tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum); if (HeapTupleIsValid(tuple)) diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index 39d80ccfba..70eb2370bb 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -51,6 +51,7 @@ #include "foreign/fdwapi.h" #include "mb/pg_wchar.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/queryjumble.h" #include "parser/parse_relation.h" #include "pgstat.h" @@ -1268,6 +1269,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo, resultRelInfo->ri_FdwState = NULL; resultRelInfo->ri_usesFdwDirectModify = false; resultRelInfo->ri_ConstraintExprs = NULL; + resultRelInfo->ri_VirGeneratedConstraintExprs = NULL; resultRelInfo->ri_GeneratedExprsI = NULL; resultRelInfo->ri_GeneratedExprsU = NULL; resultRelInfo->ri_projectReturning = NULL; @@ -1737,6 +1739,83 @@ ExecutePlan(QueryDesc *queryDesc, } +/* + * check whether the virtual generated column is null. + * Expand the generated expression and evaluate it. A return value of -1 + * indicates that the generated expression is not null, while a value greater + * than 0 signifies null. This is similar to ExecRelCheck. +*/ +static int +ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, Bitmapset *gen_virtual_cols) +{ + Relation rel = resultRelInfo->ri_RelationDesc; + TupleDesc tupdesc = RelationGetDescr(rel); + ExprContext *econtext; + MemoryContext oldContext; + int i = 0; + int attidx = -1; + int *attnums; + attnums = (int *) palloc0(bms_num_members(gen_virtual_cols) * sizeof(int)); + + if (resultRelInfo->ri_VirGeneratedConstraintExprs == NULL) + { + oldContext = MemoryContextSwitchTo(estate->es_query_cxt); + resultRelInfo->ri_VirGeneratedConstraintExprs = + (ExprState **) palloc0(bms_num_members(gen_virtual_cols) * sizeof(ExprState *)); + + while ((attidx = bms_next_member(gen_virtual_cols, attidx)) >= 0) + { + Expr *checkconstr; + NullTest *nnulltest = makeNode(NullTest); + Form_pg_attribute attr = TupleDescAttr(tupdesc, attidx -1); + + nnulltest->arg = (Expr *) makeVar(1, + attr->attnum, + attr->atttypid, + attr->atttypmod, + attr->attcollation, + 0); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + checkconstr = (Expr *) nnulltest; + checkconstr = (Expr *) expand_generated_columns_in_expr((Node *) checkconstr, rel, 1); + resultRelInfo->ri_VirGeneratedConstraintExprs[i] = ExecPrepareExpr(checkconstr, estate); + attnums[i++] = attidx; + } + MemoryContextSwitchTo(oldContext); + } + else + { + while ((attidx = bms_next_member(gen_virtual_cols, attidx)) >= 0) + attnums[i++] = attidx; + } + + /* + * We will use the EState's per-tuple context for evaluating virtual + * generated column check constraint expressions (creating it if it's not + * already there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + /* And evaluate the check constraints for virtual generated column */ + for (i = 0; i < bms_num_members(gen_virtual_cols); i++) + { + ExprState *gen_virtualnn = resultRelInfo->ri_VirGeneratedConstraintExprs[i]; + + if (gen_virtualnn && !ExecCheck(gen_virtualnn, econtext)) + return attnums[i]; + } + + /* -1 result means no error */ + return -1; +} + /* * ExecRelCheck --- check that tuple meets constraints for result relation * @@ -1972,6 +2051,8 @@ ExecConstraints(ResultRelInfo *resultRelInfo, Relation orig_rel = rel; TupleDesc orig_tupdesc = RelationGetDescr(rel); + if (att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + continue; /* * If the tuple has been routed, it's been converted to the * partition's rowtype, which might differ from the root @@ -2021,6 +2102,77 @@ ExecConstraints(ResultRelInfo *resultRelInfo, } } + /* check virtual generated column is not null or not */ + if (constr->has_not_null && constr->has_generated_virtual) + { + int attnum; + Bitmapset *vir_gencols = NULL; + char *val_desc = NULL; + Form_pg_attribute att; + + for (attnum = 1; attnum <= tupdesc->natts; attnum++) + { + att = TupleDescAttr(tupdesc, attnum - 1); + if (att->attnotnull && att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + vir_gencols = bms_add_member(vir_gencols, att->attnum); + } + attnum = -1; + + if(vir_gencols != NULL) + { + Relation orig_rel_nn = rel; + + attnum = ExecRelCheckGenVirtualNotNull(resultRelInfo, slot, estate, vir_gencols); + + if (attnum > 0) + { + /* null value on virtual generated column. now format the error message */ + if (resultRelInfo->ri_RootResultRelInfo) + { + ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; + TupleDesc old_tupdesc = RelationGetDescr(rel); + AttrMap *map; + + tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); + /* a reverse map */ + map = build_attrmap_by_name_if_req(old_tupdesc, + tupdesc, + false); + /* + * Partition-specific slot's tupdesc can't be changed, so + * allocate a new one. + */ + if (map != NULL) + slot = execute_attr_map_slot(map, slot, + MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); + modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), + ExecGetUpdatedCols(rootrel, estate)); + + rel = rootrel->ri_RelationDesc; + } + else + modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), + ExecGetUpdatedCols(resultRelInfo, estate)); + + val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), + slot, + tupdesc, + modifiedCols, + 64); + + att = TupleDescAttr(tupdesc, attnum - 1); + + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", + NameStr(att->attname), + RelationGetRelationName(orig_rel_nn)), + val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, + errtablecol(orig_rel_nn, attnum)); + } + } + } + if (rel->rd_rel->relchecks > 0) { const char *failed; diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index eb7716cd84..ba309e47f0 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -988,20 +988,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); - - /* - * TODO: Straightforward not-null constraints won't work on virtual - * generated columns, because there is no support for expanding the - * column when the constraint is checked. Maybe we could convert the - * not-null constraint into a full check constraint, so that the - * generation expression can be expanded at check time. - */ - if (column->is_not_null && column->generated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - parser_errposition(cxt->pstate, - constraint->location))); } /* diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index e2d1dc1e06..1595fae215 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -548,6 +548,8 @@ typedef struct ResultRelInfo /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_VirGeneratedConstraintExprs; /* * Arrays of stored generated columns ExprStates for INSERT/UPDATE/MERGE. */ diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 35638812be..826c76b900 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -660,28 +660,25 @@ INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails ERROR: new row for relation "gtest20c" violates check constraint "whole_row_check" DETAIL: Failing row contains (null, virtual). --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); -ERROR: not-null constraints are not supported on virtual generated columns -LINE 1: ... b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); - ^ ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21a" violates not-null constraint +DETAIL: Failing row contains (0, virtual). -- also check with table constraint syntax CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error -ERROR: not-null constraints are not supported on virtual generated columns +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error -ERROR: not-null constraints are not supported on virtual generated columns DROP TABLE gtest21ax; CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; -ERROR: not-null constraints are not supported on virtual generated columns -DETAIL: Column "b" of relation "gtest21b" is a virtual generated column. ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (0, virtual). ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); ERROR: unique constraints on virtual generated columns are not supported @@ -689,7 +686,7 @@ ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22a VALUES (3); --INSERT INTO gtest22a VALUES (4); CREATE TABLE gtest22b (a int, b int GENERATED ALWAYS AS (a / 2) VIRTUAL, PRIMARY KEY (a, b)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22b VALUES (2); --INSERT INTO gtest22b VALUES (2); -- indexes @@ -734,7 +731,7 @@ ERROR: foreign key constraints on virtual generated columns are not supported --DROP TABLE gtest23b; --DROP TABLE gtest23a; CREATE TABLE gtest23p (x int, y int GENERATED ALWAYS AS (x * 2) VIRTUAL, PRIMARY KEY (y)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest23p VALUES (1), (2), (3); CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); ERROR: relation "gtest23p" does not exist diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index 3487081391..1ac92b2204 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -332,23 +332,23 @@ ALTER TABLE gtest20c ADD CONSTRAINT whole_row_check CHECK (gtest20c IS NOT NULL) INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint -- also check with table constraint syntax CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error DROP TABLE gtest21ax; CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-02-26 07:00 ego alter <[email protected]> parent: jian he <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: ego alter @ 2025-02-26 07:00 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: pgsql-hackers Hi, I’ve had a chance to review the patch. As I am still getting familiar with executor part, questions and feedbacks could be relatively trivial. There are two minor issues i want to discuss: 1. The way of caching constraint-checking expr for virtual generated not null The existing array for caching constraint-checking expr is /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; the proposed changes for virtual generated not null in patch + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_VirGeneratedConstraintExprs; /* Could you explain the rationale behind adding this new field instead of reusing ri_ConstraintExprs? The comment suggests it’s used specifically for not null constraint-checking, but could it be extended to handle other constraints in the future as well? I assume one benefit is that it separates the handling of normal constraints from virtual ones, but I'd like to appreciate more context on the decision. 2. The naming of variable gen_virtualnn. Gen_virtualnn looks confusing at first glance. Checkconstr seems to be more straightforward. /* And evaluate the check constraints for virtual generated column */ + for (i = 0; i < bms_num_members(gen_virtual_cols); i++) + { + ExprState *gen_virtualnn = resultRelInfo->ri_VirGeneratedConstraintExprs[i]; + + if (gen_virtualnn && !ExecCheck(gen_virtualnn, econtext)) + return attnums[i]; + } + /* And evaluate the constraints */ for (i = 0; i < ncheck; i++) { ExprState *checkconstr = resultRelInfo->ri_ConstraintExprs[i]; /* * NOTE: SQL specifies that a NULL result from a constraint expression * is not to be treated as a failure. Therefore, use ExecCheck not * ExecQual. */ if (checkconstr && !ExecCheck(checkconstr, econtext)) return check[i].ccname; } /* NULL result means no error */ return NULL; Best regards, Xuneng jian he <[email protected]> 于2025年2月10日周一 21:34写道： > hi. > > Virtual generated columns committed, > > https://git.postgresql.org/cgit/postgresql.git/commit/?id=83ea6c54025bea67bcd4949a6d58d3fc11c3e21b > > This patch is for implementing not null constraints on virtual > generated columns. > > NOT NULL constraints on virtual generated columns mean that > if we INSERT a row into the table and the evaluation of the generated > expression results in a null value, > an ERRCODE_NOT_NULL_VIOLATION error will be reported. > > main gotcha is in ExecConstraints, expand the generated expression > and convert a not null constraint to a check constraint and evaluate it. > ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-06 13:44 jian he <[email protected]> parent: ego alter <[email protected]> 0 siblings, 2 replies; 60+ messages in thread From: jian he @ 2025-03-06 13:44 UTC (permalink / raw) To: ego alter <[email protected]>; +Cc: pgsql-hackers On Wed, Feb 26, 2025 at 3:01 PM ego alter <[email protected]> wrote: > > Hi, I’ve had a chance to review the patch. As I am still getting familiar with executor part, questions and feedbacks could be relatively trivial. > > There are two minor issues i want to discuss: > 1. The way of caching constraint-checking expr for virtual generated not null > The existing array for caching constraint-checking expr is > /* array of constraint-checking expr states */ > ExprState **ri_ConstraintExprs; > > the proposed changes for virtual generated not null in patch > + /* array of virtual generated not null constraint-checking expr states */ > + ExprState **ri_VirGeneratedConstraintExprs; > /* > Could you explain the rationale behind adding this new field instead of reusing ri_ConstraintExprs? The comment suggests it’s used specifically for not null constraint-checking, but could it be extended to handle other constraints in the future as well? I assume one benefit is that it separates the handling of normal constraints from virtual ones, but I'd like to appreciate more context on the decision. > it's a cache mechanism, just like ResultRelInfo.ri_ConstraintExprs you can see comments in ExecRelCheck /* * If first time through for this result relation, build expression * nodetrees for rel's constraint expressions. Keep them in the per-query * memory context so they'll survive throughout the query. */ for example: create table t(a int, check (a > 3)); insert into t values (4),(3); we need to call ExecRelCheck for values 4 and 3. The second time ExecRelCheck called for values 3, if ri_ConstraintExprs is not null then we didn't need to call ExecPrepareExpr again for the same check constraint expression. + ExprState **ri_VirGeneratedConstraintExprs; is specifically only for virtual generated columns not null constraint evaluation. Anyway, I renamed it to ri_GeneratedNotNullExprs. If you want to extend cache for other constraints in the future, you can add it to struct ResultRelInfo. Currently struct ResultRelInfo, we have ri_GeneratedExprsU, ri_GeneratedExprsI for generated expressions; ri_ConstraintExprs for check constraints. > 2. The naming of variable gen_virtualnn. > Gen_virtualnn looks confusing at first glance. Checkconstr seems to be more straightforward. > thanks. I changed it to exprstate. new patch attached. 0001 not null for virtual generated columns, some refactoring happened within ExecConstraints to avoid duplicated error handling code. 0002 and 0003 is the domain for virtual generated columns. domain can have not-null constraints, this is built on top of 0001, so I guess posting here for review should be fine? currently it works as intended. but add a virtual generated column with domain_with_constraints requires table rewrite. but some cases table scan should just be enough. some case we do need table rewrite. for example: create domain d1 as int check(value > random(min=>11::int, max=>12)); create domain d2 as int check(value > 12); create table t(a int); insert into t select g from generate_series(1, 10) g; alter table t add column b d1 generated always as (a+11) virtual; --we do need table rewrite in phase 3. alter table t add column c d2 generated always as (a + 12) virtual; --we can only do table scan in phase 3. Attachments: [text/x-patch] v2-0002-rename-ExecComputeGenerated-to-ExecComputeGenerat.patch (5.2K, ../../CACJufxGof=Tb6-AP_UdDy8By4Oi_Cgutpnodw4RLW-zNJLK+9g@mail.gmail.com/2-v2-0002-rename-ExecComputeGenerated-to-ExecComputeGenerat.patch) download | inline diff: From 5e1c83c18cd954abcbae4bd52ef9c77de1273f9c Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 6 Mar 2025 12:35:19 +0800 Subject: [PATCH v2 2/3] rename ExecComputeGenerated to ExecComputeGenerated to support virtual generated column over domain type, we actually need compute the virtual generated expression. we did it at ExecComputeGenerated for stored, we can use it for virtual. so do the rename. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/commands/copyfrom.c | 4 ++-- src/backend/executor/execReplication.c | 8 ++++---- src/backend/executor/nodeModifyTable.c | 20 ++++++++++---------- src/include/executor/nodeModifyTable.h | 5 ++--- 4 files changed, 18 insertions(+), 19 deletions(-) diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index bcf66f0adf8..7f1078dfe39 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1346,8 +1346,8 @@ CopyFrom(CopyFromState cstate) /* Compute stored generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, myslot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, myslot, + CMD_INSERT); /* * If the target is a plain table, check the constraints of diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c index 5cef54f00ed..fdc379e7a44 100644 --- a/src/backend/executor/execReplication.c +++ b/src/backend/executor/execReplication.c @@ -549,8 +549,8 @@ ExecSimpleRelationInsert(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* Check the constraints of the tuple */ if (rel->rd_att->constr) @@ -646,8 +646,8 @@ ExecSimpleRelationUpdate(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); /* Check the constraints of the tuple */ if (rel->rd_att->constr) diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index b0fe50075ad..53755ccdbad 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -517,12 +517,12 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, } /* - * Compute stored generated columns for a tuple + * Compute generated columns for a tuple. + * we might support virtual generated column in future, currently not. */ void -ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype) +ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot, CmdType cmdtype) { Relation rel = resultRelInfo->ri_RelationDesc; TupleDesc tupdesc = RelationGetDescr(rel); @@ -911,8 +911,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * If the FDW supports batching, and batching is requested, accumulate @@ -1038,8 +1038,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * Check any RLS WITH CHECK policies. @@ -2126,8 +2126,8 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); } /* diff --git a/src/include/executor/nodeModifyTable.h b/src/include/executor/nodeModifyTable.h index bf3b592e28f..de374c46d3c 100644 --- a/src/include/executor/nodeModifyTable.h +++ b/src/include/executor/nodeModifyTable.h @@ -19,9 +19,8 @@ extern void ExecInitGenerated(ResultRelInfo *resultRelInfo, EState *estate, CmdType cmdtype); -extern void ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype); +extern void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot,CmdType cmdtype); extern ModifyTableState *ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags); extern void ExecEndModifyTable(ModifyTableState *node); -- 2.34.1 [text/x-patch] v2-0003-domain-over-virtual-generated-column.patch (27.4K, ../../CACJufxGof=Tb6-AP_UdDy8By4Oi_Cgutpnodw4RLW-zNJLK+9g@mail.gmail.com/3-v2-0003-domain-over-virtual-generated-column.patch) download | inline diff: From a4a5343dfbac4130bbf6e3fb63992b8ac03591cd Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 6 Mar 2025 21:17:52 +0800 Subject: [PATCH v2 3/3] domain over virtual generated column. domain don't have constraints works just be fine. domain constraint check is happend within ExecComputeGenerated. we compute the virtual generated column in ExecComputeGenerated and discarded the value. domain_with_constaint can be element type of range, multirange, array, composite. to be bullet proof, if this column type is not type of TYPTYPE_BASE or it's a array type, then we do actlly compute the generated expression. This can have negative performance for INSERT, if vertain virtual column data types requires computation. the followig two query shows in pg_catalog, most of the system type is TYPTYPE_BASE. so i guess this compromise is fine. select count(*),typtype from pg_type where typnamespace = 11 group by 2; select typname, typrelid, pc.reltype, pc.oid, pt.oid from pg_type pt join pg_class pc on pc.oid = pt.typrelid where pt.typnamespace = 11 and pt.typtype = 'c' and pc.reltype = 0; ALTER DOMAIN ADD CONSTRAINT variant is supported. DOMAIN with default values are supported. but virtual generated column already have generated expression, so domain default expression doesn't matter. ALTER TABLE ADD VIRTUAL GENERATED COLUMN. need table rewrite to vertify new column value satisfied the generation expression. this can be reduced to table scan in some cases. TODO: deal with domain with volatile check constraints. TODO: only table rewrites in somes cases. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 11 - src/backend/commands/copyfrom.c | 5 +- src/backend/commands/tablecmds.c | 6 +- src/backend/commands/typecmds.c | 198 +++++++++++++++--- src/backend/executor/nodeModifyTable.c | 84 ++++++-- .../regress/expected/generated_virtual.out | 67 +++++- src/test/regress/sql/generated_virtual.sql | 49 ++++- 7 files changed, 345 insertions(+), 75 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index b807ab66668..39e2ac38141 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -583,17 +583,6 @@ CheckAttributeType(const char *attname, } else if (att_typtype == TYPTYPE_DOMAIN) { - /* - * Prevent virtual generated columns from having a domain type. We - * would have to enforce domain constraints when columns underlying - * the generated column change. This could possibly be implemented, - * but it's not. - */ - if (flags & CHKATYPE_IS_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("virtual generated column \"%s\" cannot have a domain type", attname)); - /* * If it's a domain, recurse to check its base type. */ diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 7f1078dfe39..b8c984e1ec2 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1343,9 +1343,10 @@ CopyFrom(CopyFromState cstate) } else { - /* Compute stored generated columns */ + /* Compute generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && - resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) + (resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored || + resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, myslot, CMD_INSERT); diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index c89f1cb9936..d314cfb8f7d 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -7453,10 +7453,14 @@ ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel, /* * Failed to use missing mode. We have to do a table rewrite * to install the value --- unless it's a virtual generated - * column. + * column. However if virtual generated column is domain with + * constraints then we have to table rewrite to evaulate the + * generation expression. (TODO, in some case, we don't need rewrite) */ if (colDef->generated != ATTRIBUTE_GENERATED_VIRTUAL) tab->rewrite |= AT_REWRITE_DEFAULT_VAL; + else if (has_domain_constraints) + tab->rewrite |= AT_REWRITE_DEFAULT_VAL; } } diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c index 3cb3ca1cca1..a247aa937f9 100644 --- a/src/backend/commands/typecmds.c +++ b/src/backend/commands/typecmds.c @@ -65,6 +65,7 @@ #include "parser/parse_expr.h" #include "parser/parse_func.h" #include "parser/parse_type.h" +#include "rewrite/rewriteHandler.h" #include "utils/builtins.h" #include "utils/fmgroids.h" #include "utils/inval.h" @@ -144,6 +145,7 @@ static void AlterTypeRecurse(Oid typeOid, bool isImplicitArray, AlterTypeRecurseParams *atparams); +static bool ValidateDomainNeedGeneratedExprs(RelToCheck *rtc); /* * DefineType * Registers a new base type. @@ -3112,6 +3114,28 @@ AlterDomainValidateConstraint(List *names, const char *constrName) return address; } +static bool +ValidateDomainNeedGeneratedExprs(RelToCheck *rtc) +{ + Relation testrel = rtc->rel; + TupleDesc tupdesc = RelationGetDescr(testrel); + + if (tupdesc->constr && tupdesc->constr->has_generated_virtual) + { + int i; + int attnum; + Form_pg_attribute attr; + for (i = 0; i < rtc->natts; i++) + { + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + return true; + } + } + return false; +} + /* * Verify that all columns currently using the domain are not null. */ @@ -3121,6 +3145,15 @@ validateDomainNotNullConstraint(Oid domainoid) List *rels; ListCell *rt; + /* + * for domain not null constraint over virtual generated column + * it maybe need it in below. + */ + EState *estate; + ExprContext *econtext; + estate = CreateExecutorState(); + econtext = GetPerTupleExprContext(estate); + /* Fetch relation list with attributes based on this domain */ /* ShareLock is sufficient to prevent concurrent data changes */ @@ -3134,6 +3167,39 @@ validateDomainNotNullConstraint(Oid domainoid) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + Form_pg_attribute attr; + ExprState **ri_GeneratedExprs; + bool need_GeneratedExprs = false; + int attnum; + + /* cacahe generated columns handling */ + need_GeneratedExprs = ValidateDomainNeedGeneratedExprs(rtc); + if (need_GeneratedExprs) + { + ri_GeneratedExprs = (ExprState **) palloc0(tupdesc->natts * sizeof(ExprState *)); + + for (int i = 0; i < rtc->natts; i++) + { + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + NullTest *nnulltest; + Expr *expr; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_column_default(testrel, attnum); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + expr = (Expr *) nnulltest; + ri_GeneratedExprs[attnum - 1] = ExecPrepareExpr(expr, estate); + } + } + } + /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3146,10 +3212,10 @@ validateDomainNotNullConstraint(Oid domainoid) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); - if (slot_attisnull(slot, attnum)) + if (slot_attisnull(slot, attnum) && attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) { /* * In principle the auxiliary information for this error @@ -3165,7 +3231,22 @@ validateDomainNotNullConstraint(Oid domainoid) RelationGetRelationName(testrel)), errtablecol(testrel, attnum))); } + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + econtext->ecxt_scantuple = slot; + Assert(ri_GeneratedExprs[attnum - 1] != NULL); + if (!ExecCheck(ri_GeneratedExprs[attnum - 1] , econtext)) + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } } + + ResetExprContext(econtext); } ExecDropSingleTupleTableSlot(slot); table_endscan(scan); @@ -3174,6 +3255,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Close each rel after processing, but keep lock */ table_close(testrel, NoLock); } + + FreeExecutorState(estate); } /* @@ -3210,6 +3293,32 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + ExprState **ri_GeneratedExprs; + bool need_GeneratedExprs = false; + Form_pg_attribute attr; + int attnum; + + /* cacahe generated columns handling */ + need_GeneratedExprs = ValidateDomainNeedGeneratedExprs(rtc); + + if (need_GeneratedExprs) + { + ri_GeneratedExprs = (ExprState **) palloc0(tupdesc->natts * sizeof(ExprState *)); + for (int i = 0; i < rtc->natts; i++) + { + Expr *gen_defexpr; + + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + + /* Fetch the GENERATED AS expression tree */ + gen_defexpr = (Expr *) build_column_default(testrel, attnum); + if (gen_defexpr == NULL) + elog(ERROR, "no generation expression found for column number %d of table \"%s\"", + attnum, RelationGetRelationName(testrel)); + ri_GeneratedExprs[attnum - 1] = ExecPrepareExpr(gen_defexpr, estate); + } + } /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3222,37 +3331,74 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; Datum d; bool isNull; Datum conResult; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); - d = slot_getattr(slot, attnum, &isNull); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); - econtext->domainValue_datum = d; - econtext->domainValue_isNull = isNull; - - conResult = ExecEvalExprSwitchContext(exprstate, - econtext, - &isNull); - - if (!isNull && !DatumGetBool(conResult)) + /* + * we first actually compute the virtual generated column value + * then do the CoerceToDomainValue check. + */ + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { + Datum ret; + bool isnull; + + econtext = GetPerTupleExprContext(estate); + econtext->ecxt_scantuple = slot; + + ret = ExecEvalExprSwitchContext(ri_GeneratedExprs[attnum - 1], + econtext, + &isnull); /* - * In principle the auxiliary information for this error - * should be errdomainconstraint(), but errtablecol() - * seems considerably more useful in practice. Since this - * code only executes in an ALTER DOMAIN command, the - * client should already know which domain is in question, - * and which constraint too. + * we probally don't need datumCopy to copy ret, since here + * we just check the value. */ - ereport(ERROR, - (errcode(ERRCODE_CHECK_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + econtext->domainValue_datum = ret; + econtext->domainValue_isNull = isnull; + econtext->ecxt_scantuple = NULL; + + conResult = ExecEvalExprSwitchContext(exprstate, + econtext, + &isNull); + if (!isNull && !DatumGetBool(conResult)) + ereport(ERROR, + errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } + else + { + d = slot_getattr(slot, attnum, &isNull); + + econtext->domainValue_datum = d; + econtext->domainValue_isNull = isNull; + + conResult = ExecEvalExprSwitchContext(exprstate, + econtext, + &isNull); + + if (!isNull && !DatumGetBool(conResult)) + { + /* + * In principle the auxiliary information for this error + * should be errdomainconstraint(), but errtablecol() + * seems considerably more useful in practice. Since this + * code only executes in an ALTER DOMAIN command, the + * client should already know which domain is in question, + * and which constraint too. + */ + ereport(ERROR, + (errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + } } } diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 53755ccdbad..e83e57bea0a 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -67,6 +67,7 @@ #include "storage/lmgr.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/lsyscache.h" #include "utils/rel.h" #include "utils/snapmgr.h" @@ -395,7 +396,7 @@ ExecCheckTIDVisible(EState *estate, * * This fills the resultRelInfo's ri_GeneratedExprsI/ri_NumGeneratedNeededI or * ri_GeneratedExprsU/ri_NumGeneratedNeededU fields, depending on cmdtype. - * This is used only for stored generated columns. + * This is used for stored and virtual generated columns. * * If cmdType == CMD_UPDATE, the ri_extraUpdatedCols field is filled too. * This is used by both stored and virtual generated columns. @@ -477,6 +478,33 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); ri_NumGeneratedNeeded++; } + else + { + /* + * Virtual generated columns only need to be computed when the + * type is domain_with_constraint. However, + * domain_with_constraint can be the element type of a range, the + * element type of a composite, or the element type of an array. + * + * To determine whether the true base element type is + * domain_with_constraint, multiple lookup_type_cache calls seems + * doable. However, this would add a lot of code. + * So, simplified it: only if the type is TYPTYPE_BASE and it's + * not an array type, computation is not needed. + */ + Oid typelem = InvalidOid; + Oid atttypid = TupleDescAttr(tupdesc, i)->atttypid; + char att_typtype = get_typtype(atttypid); + + if (att_typtype == TYPTYPE_BASE) + typelem = get_element_type(atttypid); + + if (att_typtype != TYPTYPE_BASE || OidIsValid(typelem)) + { + ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); + ri_NumGeneratedNeeded++; + } + } /* If UPDATE, mark column in resultRelInfo->ri_extraUpdatedCols */ if (cmdtype == CMD_UPDATE) @@ -518,7 +546,9 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, /* * Compute generated columns for a tuple. - * we might support virtual generated column in future, currently not. + * Generally, we don't need compute virtual generated column, except for column + * type is domain with constraint. Since virtual generated column don't have + * storage, we don't need stored the computed value. */ void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, @@ -532,9 +562,11 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, MemoryContext oldContext; Datum *values; bool *nulls; + bool need_compute = false; /* We should not be called unless this is true */ - Assert(tupdesc->constr && tupdesc->constr->has_generated_stored); + Assert(tupdesc->constr); + Assert(tupdesc->constr->has_generated_stored || tupdesc->constr->has_generated_virtual); /* * Initialize the expressions if we didn't already, and check whether we @@ -553,7 +585,8 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, if (resultRelInfo->ri_GeneratedExprsI == NULL) ExecInitGenerated(resultRelInfo, estate, cmdtype); /* Early exit is impossible given the prior Assert */ - Assert(resultRelInfo->ri_NumGeneratedNeededI > 0); + if (resultRelInfo->ri_GeneratedExprsI != NULL) + Assert(resultRelInfo->ri_NumGeneratedNeededI > 0); ri_GeneratedExprs = resultRelInfo->ri_GeneratedExprsI; } @@ -565,30 +598,40 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, slot_getallattrs(slot); memcpy(nulls, slot->tts_isnull, sizeof(*nulls) * natts); + need_compute = (resultRelInfo->ri_NumGeneratedNeededI > 0 || + resultRelInfo->ri_NumGeneratedNeededU > 0); + for (int i = 0; i < natts; i++) { CompactAttribute *attr = TupleDescCompactAttr(tupdesc, i); - if (ri_GeneratedExprs[i]) + if (need_compute && ri_GeneratedExprs[i] ) { Datum val; bool isnull; - Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED); - econtext->ecxt_scantuple = slot; val = ExecEvalExpr(ri_GeneratedExprs[i], econtext, &isnull); - /* - * We must make a copy of val as we have no guarantees about where - * memory for a pass-by-reference Datum is located. - */ - if (!isnull) - val = datumCopy(val, attr->attbyval, attr->attlen); + if (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED) + { + /* + * We must make a copy of val as we have no guarantees about where + * memory for a pass-by-reference Datum is located. + */ + if (!isnull) + val = datumCopy(val, attr->attbyval, attr->attlen); - values[i] = val; - nulls[i] = isnull; + values[i] = val; + nulls[i] = isnull; + } + else + { + Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + values[i] = (Datum) 0; + nulls[i] = true; + } } else { @@ -910,7 +953,8 @@ ExecInsert(ModifyTableContext *context, * Compute stored generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -1037,7 +1081,8 @@ ExecInsert(ModifyTableContext *context, * Compute stored generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -2122,10 +2167,11 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, slot->tts_tableOid = RelationGetRelid(resultRelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_UPDATE); } diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 3bd5130587c..c1528477cea 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -763,16 +763,65 @@ ERROR: relation "gtest23p" does not exist --INSERT INTO gtest23q VALUES (1, 2); -- ok --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +UPDATE gtest24 SET a = 6; -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +COPY gtest24 FROM stdin; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +CONTEXT: COPY gtest24, line 1: "6" +SELECT * FROM gtest24; + a | b +---+--- + 4 | 8 + 3 | 6 + | +(3 rows) + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ERROR: column "c" of relation "gtest24" contains null values +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +ERROR: column "b" of table "gtest24" contains null values +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok +INSERT INTO gtest24 (a) VALUES (NULL); -- error +ERROR: domain gtestdomain1 does not allow null values CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +INSERT INTO gtest24r (a) VALUES (5); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check2" +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +ERROR: null value in column "c" of relation "gtest24v" violates not-null constraint +DETAIL: Failing row contains ({"a": [6, -1], "b": [6, 10]}, virtual, virtual). +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); CREATE TABLE gtest28 OF gtest_type (f1 WITH OPTIONS GENERATED ALWAYS AS (f2 *2) VIRTUAL); diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index f436e8f2313..0b3a981f225 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -429,14 +429,49 @@ CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +UPDATE gtest24 SET a = 6; -- error +COPY gtest24 FROM stdin; --error +6 +\. + +SELECT * FROM gtest24; + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok + +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok + +INSERT INTO gtest24 (a) VALUES (NULL); -- error + CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +INSERT INTO gtest24r (a) VALUES (5); -- error + +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); -- 2.34.1 [text/x-patch] v2-0001-not-null-for-virtual-generated-column.patch (22.9K, ../../CACJufxGof=Tb6-AP_UdDy8By4Oi_Cgutpnodw4RLW-zNJLK+9g@mail.gmail.com/4-v2-0001-not-null-for-virtual-generated-column.patch) download | inline diff: From ea676b927f0d74c1dde6237cd2f5b613af44053d Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 6 Mar 2025 12:01:31 +0800 Subject: [PATCH v2 1/3] not null for virtual generated column now we can add not null constraint on virtual generated column. not null constraint on virtual generated column make sure evaulation of the expanded generated expression does not yield null. the virtual generated columns does not store value, the storage is null. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 10 - src/backend/commands/indexcmds.c | 10 +- src/backend/commands/tablecmds.c | 8 - src/backend/executor/execMain.c | 234 ++++++++++++++---- src/backend/parser/parse_utilcmd.c | 14 -- src/include/nodes/execnodes.h | 2 + .../regress/expected/generated_virtual.out | 54 ++-- src/test/regress/sql/generated_virtual.sql | 31 ++- 8 files changed, 247 insertions(+), 116 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index bd3554c0bfd..b807ab66668 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -2615,11 +2615,6 @@ AddRelationNewConstraints(Relation rel, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(cdef->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), colnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * If the column already has a not-null constraint, we don't want @@ -2935,11 +2930,6 @@ AddRelationNotNullConstraints(Relation rel, List *constraints, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(constr->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), attnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * A column can only have one not-null constraint, so discard any diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 32ff3ca9a28..e690487eb3e 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -1126,10 +1126,12 @@ DefineIndex(Oid tableId, if (TupleDescAttr(RelationGetDescr(rel), attno - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - stmt->isconstraint ? - errmsg("unique constraints on virtual generated columns are not supported") : - errmsg("indexes on virtual generated columns are not supported"))); + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + stmt->primary ? + errmsg("primary key on virtual generated columns are not supported") : + stmt->isconstraint ? + errmsg("unique constraints on virtual generated columns are not supported") : + errmsg("indexes on virtual generated columns are not supported")); } /* diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 59156a1c1f6..c89f1cb9936 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -7824,14 +7824,6 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName, errmsg("cannot alter system column \"%s\"", colName))); - /* TODO: see transformColumnDefinition() */ - if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", - colName, RelationGetRelationName(rel)))); - /* See if there's already a constraint */ tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum); if (HeapTupleIsValid(tuple)) diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index 0493b7d5365..5f0b0cc3b8e 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -51,6 +51,7 @@ #include "foreign/fdwapi.h" #include "mb/pg_wchar.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/queryjumble.h" #include "parser/parse_relation.h" #include "pgstat.h" @@ -1372,6 +1373,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo, resultRelInfo->ri_FdwState = NULL; resultRelInfo->ri_usesFdwDirectModify = false; resultRelInfo->ri_ConstraintExprs = NULL; + resultRelInfo->ri_GeneratedNotNullExprs = NULL; resultRelInfo->ri_GeneratedExprsI = NULL; resultRelInfo->ri_GeneratedExprsU = NULL; resultRelInfo->ri_projectReturning = NULL; @@ -1841,6 +1843,78 @@ ExecutePlan(QueryDesc *queryDesc, } +/* + * we warp "col IS NOT NULL" to a NullTest node. NullTest->arg is the virtual + * generated expression. + * A return value of -1 means virtual generated not null constraint satisfied, + * return value > 0 means not null violation happend in that attribute number. + * + * gen_virtual_cols is the attribute numbers of virtual generated column. +*/ +static int +ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, Bitmapset *gen_virtual_cols) +{ + Relation rel = resultRelInfo->ri_RelationDesc; + ExprContext *econtext; + MemoryContext oldContext; + int i = 0; + int attidx = -1; + int *attnums; + int cnt = bms_num_members(gen_virtual_cols); + + attnums = (int *) palloc0(cnt * sizeof(int)); + if (resultRelInfo->ri_GeneratedNotNullExprs == NULL) + { + oldContext = MemoryContextSwitchTo(estate->es_query_cxt); + resultRelInfo->ri_GeneratedNotNullExprs = + (ExprState **) palloc0(cnt * sizeof(ExprState *)); + + while ((attidx = bms_next_member(gen_virtual_cols, attidx)) >= 0) + { + Expr *expr; + NullTest *nnulltest; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_generation_expression(rel, attidx); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + expr = (Expr *) nnulltest; + resultRelInfo->ri_GeneratedNotNullExprs[i] = ExecPrepareExpr(expr, estate); + attnums[i++] = attidx; + } + MemoryContextSwitchTo(oldContext); + } + else + { + while ((attidx = bms_next_member(gen_virtual_cols, attidx)) >= 0) + attnums[i++] = attidx; + } + + /* + * We will use the EState's per-tuple context for evaluating virtual + * generated column not null constraint expressions (creating it if it's not + * already there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + /* And evaluate the check constraints for virtual generated column */ + for (i = 0; i < cnt; i++) + { + ExprState *exprstate = resultRelInfo->ri_GeneratedNotNullExprs[i]; + if (exprstate && !ExecCheck(exprstate, econtext)) + return attnums[i]; + } + + /* -1 result means no error */ + return -1; +} + /* * ExecRelCheck --- check that tuple meets constraints for result relation * @@ -2039,6 +2113,70 @@ ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, errtable(resultRelInfo->ri_RelationDesc))); } +/* not null constraint violation happened, now format the error message */ +static void +NotNullViolationErrorReport(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, int attrChk) +{ + Bitmapset *modifiedCols; + char *val_desc; + + Relation rel = resultRelInfo->ri_RelationDesc; + Relation orig_rel = rel; + + TupleDesc tupdesc = RelationGetDescr(rel); + TupleDesc orig_tupdesc = RelationGetDescr(rel); + Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + + Assert(attrChk > 0); + + /* + * If the tuple has been routed, it's been converted to the + * partition's rowtype, which might differ from the root + * table's. We must convert it back to the root table's + * rowtype so that val_desc shown error message matches the + * input tuple. + */ + if (resultRelInfo->ri_RootResultRelInfo) + { + ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; + AttrMap *map; + + tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); + /* a reverse map */ + map = build_attrmap_by_name_if_req(orig_tupdesc, + tupdesc, + false); + + /* + * Partition-specific slot's tupdesc can't be changed, so + * allocate a new one. + */ + if (map != NULL) + slot = execute_attr_map_slot(map, slot, + MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); + modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), + ExecGetUpdatedCols(rootrel, estate)); + rel = rootrel->ri_RelationDesc; + } + else + modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), + ExecGetUpdatedCols(resultRelInfo, estate)); + + val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), + slot, + tupdesc, + modifiedCols, + 64); + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", + NameStr(att->attname), + RelationGetRelationName(orig_rel)), + val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, + errtablecol(orig_rel, attrChk)); +} + /* * ExecConstraints - check constraints of the tuple in 'slot' * @@ -2058,73 +2196,63 @@ ExecConstraints(ResultRelInfo *resultRelInfo, TupleDesc tupdesc = RelationGetDescr(rel); TupleConstr *constr = tupdesc->constr; Bitmapset *modifiedCols; + bool virtual_notnull = false; + Form_pg_attribute att; + int natts; + int attnum; Assert(constr); /* we should not be called otherwise */ + natts = tupdesc->natts; if (constr->has_not_null) { - int natts = tupdesc->natts; - int attrChk; - - for (attrChk = 1; attrChk <= natts; attrChk++) + for (attnum = 1; attnum <= natts; attnum++) { - Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + att = TupleDescAttr(tupdesc, attnum - 1); - if (att->attnotnull && slot_attisnull(slot, attrChk)) + if (att->attnotnull && slot_attisnull(slot, attnum)) { - char *val_desc; - Relation orig_rel = rel; - TupleDesc orig_tupdesc = RelationGetDescr(rel); - - /* - * If the tuple has been routed, it's been converted to the - * partition's rowtype, which might differ from the root - * table's. We must convert it back to the root table's - * rowtype so that val_desc shown error message matches the - * input tuple. - */ - if (resultRelInfo->ri_RootResultRelInfo) + /* virtual generated column not null constraint handled below */ + if (att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { - ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; - AttrMap *map; - - tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); - /* a reverse map */ - map = build_attrmap_by_name_if_req(orig_tupdesc, - tupdesc, - false); - - /* - * Partition-specific slot's tupdesc can't be changed, so - * allocate a new one. - */ - if (map != NULL) - slot = execute_attr_map_slot(map, slot, - MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); - modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), - ExecGetUpdatedCols(rootrel, estate)); - rel = rootrel->ri_RelationDesc; + if (!virtual_notnull) + virtual_notnull = true; + continue; } - else - modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), - ExecGetUpdatedCols(resultRelInfo, estate)); - val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), - slot, - tupdesc, - modifiedCols, - 64); - - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", - NameStr(att->attname), - RelationGetRelationName(orig_rel)), - val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, - errtablecol(orig_rel, attrChk))); + NotNullViolationErrorReport(resultRelInfo, slot, estate, attnum); } } } + /* check virtual generated column not null constraint */ + if (virtual_notnull) + { + Bitmapset *vir_gencols = NULL; + + Assert(constr->has_not_null); + Assert(constr->has_generated_virtual); + + for (attnum = 1; attnum <= natts; attnum++) + { + att = TupleDescAttr(tupdesc, attnum - 1); + if (att->attnotnull && att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + vir_gencols = bms_add_member(vir_gencols, att->attnum); + } + attnum = -1; + Assert(vir_gencols != NULL); + + attnum = ExecRelCheckGenVirtualNotNull(resultRelInfo, slot, estate, vir_gencols); + + /* constraint evaulation return falsem do error report, also make an Assert */ + if (attnum > 0) + { + att = TupleDescAttr(tupdesc, attnum - 1); + Assert(att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + + NotNullViolationErrorReport(resultRelInfo, slot, estate, attnum); + } + } + if (rel->rd_rel->relchecks > 0) { const char *failed; diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index abbe1bb45a3..7e9a5f7411b 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -988,20 +988,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); - - /* - * TODO: Straightforward not-null constraints won't work on virtual - * generated columns, because there is no support for expanding the - * column when the constraint is checked. Maybe we could convert the - * not-null constraint into a full check constraint, so that the - * generation expression can be expanded at check time. - */ - if (column->is_not_null && column->generated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - parser_errposition(cxt->pstate, - constraint->location))); } /* diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index a323fa98bbb..1c72243468c 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -549,6 +549,8 @@ typedef struct ResultRelInfo /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_GeneratedNotNullExprs; /* * Arrays of stored generated columns ExprStates for INSERT/UPDATE/MERGE. */ diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 7ef05f45be7..3bd5130587c 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -664,28 +664,46 @@ INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails ERROR: new row for relation "gtest20c" violates check constraint "whole_row_check" DETAIL: Failing row contains (null, virtual). --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); -ERROR: not-null constraints are not supported on virtual generated columns -LINE 1: ... b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); - ^ ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21a" violates not-null constraint +DETAIL: Failing row contains (0, virtual). -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error -ERROR: not-null constraints are not supported on virtual generated columns +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21ax (a) VALUES (1); --ok +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error -ERROR: not-null constraints are not supported on virtual generated columns +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; -ERROR: not-null constraints are not supported on virtual generated columns -DETAIL: Column "b" of relation "gtest21b" is a virtual generated column. ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21b (a) VALUES (NULL); -- error +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (null, virtual). ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (f2 * 2) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (1, NULL); +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (1, null, virtual). +INSERT INTO gtestnn_parent VALUES (5, NULL); +ERROR: null value in column "f3" of relation "gtestnn_childdef" violates not-null constraint +DETAIL: Failing row contains (5, null, virtual). -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); ERROR: unique constraints on virtual generated columns are not supported @@ -693,7 +711,7 @@ ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22a VALUES (3); --INSERT INTO gtest22a VALUES (4); CREATE TABLE gtest22b (a int, b int GENERATED ALWAYS AS (a / 2) VIRTUAL, PRIMARY KEY (a, b)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary key on virtual generated columns are not supported --INSERT INTO gtest22b VALUES (2); --INSERT INTO gtest22b VALUES (2); -- indexes @@ -738,7 +756,7 @@ ERROR: foreign key constraints on virtual generated columns are not supported --DROP TABLE gtest23b; --DROP TABLE gtest23a; CREATE TABLE gtest23p (x int, y int GENERATED ALWAYS AS (x * 2) VIRTUAL, PRIMARY KEY (y)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary key on virtual generated columns are not supported --INSERT INTO gtest23p VALUES (1), (2), (3); CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); ERROR: relation "gtest23p" does not exist diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index dab8c92ef99..f436e8f2313 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -335,23 +335,36 @@ ALTER TABLE gtest20c ADD CONSTRAINT whole_row_check CHECK (gtest20c IS NOT NULL) INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +INSERT INTO gtest21ax (a) VALUES (1); --ok +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (NULL); -- error ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now + +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (f2 * 2) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (1, NULL); +INSERT INTO gtestnn_parent VALUES (5, NULL); + -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-07 16:47 Navneet Kumar <[email protected]> parent: jian he <[email protected]> 1 sibling, 1 reply; 60+ messages in thread From: Navneet Kumar @ 2025-03-07 16:47 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: ego alter <[email protected]>; pgsql-hackers Hi I encountered an issue when trying to add a virtual column to an existing table using the ALTER command. The operation fails even though the existing data ensures that the virtual column's value will never be NULL. However, if I define the same virtual column while creating the table and then insert the same data, it works as expected. For example This scenario fails 1. CREATE TABLE person ( id INT GENERATED BY DEFAULT AS IDENTITY, first_name VARCHAR(50) NOT NULL, last_name VARCHAR(50) NOT NULL ); 2. INSERT INTO person (first_name, last_name) VALUES ('first', 'last'); 3. ALTER TABLE person ADD COLUMN full_name VARCHAR(100) GENERATED ALWAYS AS (first_name || ' ' || last_name) VIRTUAL; The above ALTER command works if I use STORED instead. Also if I define virtual generated column while creating table it works with same data. 1. CREATE TABLE person ( id INT GENERATED BY DEFAULT AS IDENTITY, first_name VARCHAR(50) NOT NULL, last_name VARCHAR(50) NOT NULL, full_name VARCHAR(100) NOT NULL GENERATED ALWAYS AS (first_name || ' ' || last_name) VIRTUAL ); 2. INSERT INTO person(first_name, last_name) VALUES ('first', 'last'); On Thu, Mar 6, 2025 at 7:15 PM jian he <[email protected]> wrote: > On Wed, Feb 26, 2025 at 3:01 PM ego alter <[email protected]> wrote: > > > > Hi, I’ve had a chance to review the patch. As I am still getting > familiar with executor part, questions and feedbacks could be relatively > trivial. > > > > There are two minor issues i want to discuss: > > 1. The way of caching constraint-checking expr for virtual generated not > null > > The existing array for caching constraint-checking expr is > > /* array of constraint-checking expr states */ > > ExprState **ri_ConstraintExprs; > > > > the proposed changes for virtual generated not null in patch > > + /* array of virtual generated not null constraint-checking expr > states */ > > + ExprState **ri_VirGeneratedConstraintExprs; > > /* > > Could you explain the rationale behind adding this new field instead of > reusing ri_ConstraintExprs? The comment suggests it’s used specifically for > not null constraint-checking, but could it be extended to handle other > constraints in the future as well? I assume one benefit is that it > separates the handling of normal constraints from virtual ones, but I'd > like to appreciate more context on the decision. > > > > it's a cache mechanism, just like ResultRelInfo.ri_ConstraintExprs > you can see comments in ExecRelCheck > /* > * If first time through for this result relation, build expression > * nodetrees for rel's constraint expressions. Keep them in the > per-query > * memory context so they'll survive throughout the query. > */ > > for example: > create table t(a int, check (a > 3)); > insert into t values (4),(3); > we need to call ExecRelCheck for values 4 and 3. > The second time ExecRelCheck called for values 3, if > ri_ConstraintExprs is not null then > we didn't need to call ExecPrepareExpr again for the same check > constraint expression. > > + ExprState **ri_VirGeneratedConstraintExprs; > is specifically only for virtual generated columns not null constraint > evaluation. > Anyway, I renamed it to ri_GeneratedNotNullExprs. > > If you want to extend cache for other constraints in the future, > you can add it to struct ResultRelInfo. > Currently struct ResultRelInfo, we have ri_GeneratedExprsU, > ri_GeneratedExprsI for generated expressions; > ri_ConstraintExprs for check constraints. > > > > 2. The naming of variable gen_virtualnn. > > Gen_virtualnn looks confusing at first glance. Checkconstr seems to be > more straightforward. > > > thanks. I changed it to exprstate. > > new patch attached. > 0001 not null for virtual generated columns, some refactoring happened > within ExecConstraints > to avoid duplicated error handling code. > > 0002 and 0003 is the domain for virtual generated columns. domain can > have not-null constraints, > this is built on top of 0001, so I guess posting here for review should be > fine? > > currently it works as intended. but add a virtual generated column > with domain_with_constraints > requires table rewrite. but some cases table scan should just be enough. > some case we do need table rewrite. > for example: > create domain d1 as int check(value > random(min=>11::int, max=>12)); > create domain d2 as int check(value > 12); > create table t(a int); > insert into t select g from generate_series(1, 10) g; > alter table t add column b d1 generated always as (a+11) virtual; --we > do need table rewrite in phase 3. > alter table t add column c d2 generated always as (a + 12) virtual; > --we can only do table scan in phase 3. > ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-07 18:09 Navneet Kumar <[email protected]> parent: Navneet Kumar <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: Navneet Kumar @ 2025-03-07 18:09 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: ego alter <[email protected]>; pgsql-hackers > > This scenario fails > 1. CREATE TABLE person ( > id INT GENERATED BY DEFAULT AS IDENTITY, > first_name VARCHAR(50) NOT NULL, > last_name VARCHAR(50) NOT NULL > ); > > 2. INSERT INTO person (first_name, last_name) > VALUES ('first', 'last'); > > 3. ALTER TABLE person > ADD COLUMN full_name VARCHAR(100) GENERATED ALWAYS AS (first_name || ' ' > || last_name) VIRTUAL; > Forgot to mention NOT NULL constraint in above query. 3. ALTER TABLE person ADD COLUMN full_name VARCHAR(100) NOT NULL GENERATED ALWAYS AS (first_name || ' ' || last_name) VIRTUAL; ERROR: column "full_name" of relation "person" contains null values ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-08 04:23 Xuneng Zhou <[email protected]> parent: jian he <[email protected]> 1 sibling, 0 replies; 60+ messages in thread From: Xuneng Zhou @ 2025-03-08 04:23 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: Navneet Kumar <[email protected]>; [email protected] Hi, jian he <[email protected]> 于2025年3月6日周四 21:44写道： > On Wed, Feb 26, 2025 at 3:01 PM ego alter <[email protected]> wrote: > > > > Hi, I’ve had a chance to review the patch. As I am still getting > familiar with executor part, questions and feedbacks could be relatively > trivial. > > > > There are two minor issues i want to discuss: > > 1. The way of caching constraint-checking expr for virtual generated not > null > > The existing array for caching constraint-checking expr is > > /* array of constraint-checking expr states */ > > ExprState **ri_ConstraintExprs; > > > > the proposed changes for virtual generated not null in patch > > + /* array of virtual generated not null constraint-checking expr > states */ > > + ExprState **ri_VirGeneratedConstraintExprs; > > /* > > Could you explain the rationale behind adding this new field instead of > reusing ri_ConstraintExprs? The comment suggests it’s used specifically for > not null constraint-checking, but could it be extended to handle other > constraints in the future as well? I assume one benefit is that it > separates the handling of normal constraints from virtual ones, but I'd > like to appreciate more context on the decision. > > > > it's a cache mechanism, just like ResultRelInfo.ri_ConstraintExprs > you can see comments in ExecRelCheck > /* > * If first time through for this result relation, build expression > * nodetrees for rel's constraint expressions. Keep them in the > per-query > * memory context so they'll survive throughout the query. > */ > > for example: > create table t(a int, check (a > 3)); > insert into t values (4),(3); > we need to call ExecRelCheck for values 4 and 3. > The second time ExecRelCheck called for values 3, if > ri_ConstraintExprs is not null then > we didn't need to call ExecPrepareExpr again for the same check > constraint expression. > > + ExprState **ri_VirGeneratedConstraintExprs; > is specifically only for virtual generated columns not null constraint > evaluation. > Anyway, I renamed it to ri_GeneratedNotNullExprs. > > If you want to extend cache for other constraints in the future, > you can add it to struct ResultRelInfo. > Currently struct ResultRelInfo, we have ri_GeneratedExprsU, > ri_GeneratedExprsI for generated expressions; > ri_ConstraintExprs for check constraints. > > Thank you for your explanation! This name seems to be more clear for its usage. > > > 2. The naming of variable gen_virtualnn. > > Gen_virtualnn looks confusing at first glance. Checkconstr seems to be > more straightforward. > > > thanks. I changed it to exprstate. > > new patch attached. > 0001 not null for virtual generated columns, some refactoring happened > within ExecConstraints > to avoid duplicated error handling code. > > 0002 and 0003 is the domain for virtual generated columns. domain can > have not-null constraints, > this is built on top of 0001, so I guess posting here for review should be > fine? > > currently it works as intended. but add a virtual generated column > with domain_with_constraints > requires table rewrite. but some cases table scan should just be enough. > some case we do need table rewrite. > for example: > create domain d1 as int check(value > random(min=>11::int, max=>12)); > create domain d2 as int check(value > 12); > create table t(a int); > insert into t select g from generate_series(1, 10) g; > alter table t add column b d1 generated always as (a+11) virtual; --we > do need table rewrite in phase 3. > alter table t add column c d2 generated always as (a + 12) virtual; > --we can only do table scan in phase 3. > ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-08 04:30 Xuneng Zhou <[email protected]> parent: Navneet Kumar <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: Xuneng Zhou @ 2025-03-08 04:30 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: Navneet Kumar <[email protected]>; [email protected] Hi, forget to add hackers to cc. Xuneng Zhou <[email protected]> 于2025年3月8日周六 12:10写道： > > > Navneet Kumar <[email protected]> 于2025年3月8日周六 02:09写道： > >> >> >>> This scenario fails >>> 1. CREATE TABLE person ( >>> id INT GENERATED BY DEFAULT AS IDENTITY, >>> first_name VARCHAR(50) NOT NULL, >>> last_name VARCHAR(50) NOT NULL >>> ); >>> >>> 2. INSERT INTO person (first_name, last_name) >>> VALUES ('first', 'last'); >>> >>> 3. ALTER TABLE person >>> ADD COLUMN full_name VARCHAR(100) GENERATED ALWAYS AS (first_name || ' ' >>> || last_name) VIRTUAL; >>> >> >> Forgot to mention NOT NULL constraint in above query. >> >> 3. ALTER TABLE person >> ADD COLUMN full_name VARCHAR(100) NOT NULL GENERATED ALWAYS AS >> (first_name || ' ' || last_name) VIRTUAL; >> >> ERROR: column "full_name" of relation "person" contains null values >> >> > > I did some debugging for this error. It is reported in this function: > > */** > > * * ATRewriteTable: scan or rewrite one table* > > * ** > > * * A rewrite is requested by passing a valid OIDNewHeap; in that case, > caller* > > * * must already hold AccessExclusiveLock on it.* > > * */* > > static void > > *ATRewriteTable*(AlteredTableInfo **tab*, Oid *OIDNewHeap*) > > { > > > > ....... > > > * /* Now check any constraints on the possibly-changed tuple */* > > econtext->ecxt_scantuple = insertslot; > > > foreach(l, notnull_attrs) > > { > > int attn = lfirst_int(l); > > > if (*slot_attisnull*(insertslot, attn + 1)) > > { > > Form_pg_attribute attr = *TupleDescAttr*(newTupDesc, > attn); > > > ereport(ERROR, > > (*errcode*(ERRCODE_NOT_NULL_VIOLATION), > > *errmsg*("column \"%s\" of relation \"%s\" > contains null values", > > NameStr(attr->attname), > > RelationGetRelationName(oldrel)), > > *errtablecol*(oldrel, attn + 1))); > > } > > } > > ....... > > } > > > If this error is unexpected, I think the issue is that when adding a NOT > NULL constraint to a regular column, pg scans the table to ensure no NULL > values exist. But for virtual columns, there are no stored values to scan. > Maybe we should add some condition like this? Then checking not null at > runtime. > > > * /* Skip NOT NULL validation for virtual generated columns during table > rewrite */* > > if (TupleDescAttr(newTupDesc, attn)->attgenerated == > ATTRIBUTE_GENERATED_VIRTUAL) > > continue; > ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-08 10:10 jian he <[email protected]> parent: Xuneng Zhou <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: jian he @ 2025-03-08 10:10 UTC (permalink / raw) To: Xuneng Zhou <[email protected]>; +Cc: Navneet Kumar <[email protected]>; [email protected] hi. patch attached to fix the above thread mentioned issue, related tests added. also there are several compiler warnings at [0] for virtual generated column domain patch, i did some minor adjustment, let's see how it goes. [0] https://cirrus-ci.com/task/4550600270020608 Attachments: [text/x-patch] v3-0003-domain-over-virtual-generated-column.patch (27.9K, ../../CACJufxFT3+0iY6aj4GYqi1kOdgvKP3teXT-1RrYagxhJKfxRTw@mail.gmail.com/2-v3-0003-domain-over-virtual-generated-column.patch) download | inline diff: From 0985d7a779287feaa1a382726e566418bc56d381 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Sat, 8 Mar 2025 18:08:51 +0800 Subject: [PATCH v3 3/3] domain over virtual generated column. domain don't have constraints works just be fine. domain constraint check is happend within ExecComputeGenerated. we compute the virtual generated column in ExecComputeGenerated and discarded the value. domain_with_constaint can be element type of range, multirange, array, composite. to be bullet proof, if this column type is not type of TYPTYPE_BASE or it's a array type, then we do actlly compute the generated expression. This can have negative performance for INSERT, if vertain virtual column data types requires computation. the followig two query shows in pg_catalog, most of the system type is TYPTYPE_BASE. so i guess this compromise is fine. select count(*),typtype from pg_type where typnamespace = 11 group by 2; select typname, typrelid, pc.reltype, pc.oid, pt.oid from pg_type pt join pg_class pc on pc.oid = pt.typrelid where pt.typnamespace = 11 and pt.typtype = 'c' and pc.reltype = 0; ALTER DOMAIN ADD CONSTRAINT variant is supported. DOMAIN with default values are supported. but virtual generated column already have generated expression, so domain default expression doesn't matter. ALTER TABLE ADD VIRTUAL GENERATED COLUMN. need table rewrite to vertify new column value satisfied the generation expression. this can be reduced to table scan in some cases. TODO: deal with domain with volatile check constraints. TODO: only table rewrites in somes cases. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 11 - src/backend/commands/copyfrom.c | 5 +- src/backend/commands/tablecmds.c | 6 +- src/backend/commands/typecmds.c | 210 +++++++++++++++--- src/backend/executor/nodeModifyTable.c | 84 +++++-- .../regress/expected/generated_virtual.out | 67 +++++- src/test/regress/sql/generated_virtual.sql | 49 +++- 7 files changed, 352 insertions(+), 80 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index b807ab66668..39e2ac38141 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -583,17 +583,6 @@ CheckAttributeType(const char *attname, } else if (att_typtype == TYPTYPE_DOMAIN) { - /* - * Prevent virtual generated columns from having a domain type. We - * would have to enforce domain constraints when columns underlying - * the generated column change. This could possibly be implemented, - * but it's not. - */ - if (flags & CHKATYPE_IS_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("virtual generated column \"%s\" cannot have a domain type", attname)); - /* * If it's a domain, recurse to check its base type. */ diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 7f1078dfe39..b8c984e1ec2 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1343,9 +1343,10 @@ CopyFrom(CopyFromState cstate) } else { - /* Compute stored generated columns */ + /* Compute generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && - resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) + (resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored || + resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, myslot, CMD_INSERT); diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 41efda3d338..55411d3d5e1 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -7510,10 +7510,14 @@ ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel, /* * Failed to use missing mode. We have to do a table rewrite * to install the value --- unless it's a virtual generated - * column. + * column. However if virtual generated column is domain with + * constraints then we have to table rewrite to evaulate the + * generation expression. (TODO, in some case, we don't need rewrite) */ if (colDef->generated != ATTRIBUTE_GENERATED_VIRTUAL) tab->rewrite |= AT_REWRITE_DEFAULT_VAL; + else if (has_domain_constraints) + tab->rewrite |= AT_REWRITE_DEFAULT_VAL; } } diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c index 3cb3ca1cca1..7ef84700619 100644 --- a/src/backend/commands/typecmds.c +++ b/src/backend/commands/typecmds.c @@ -65,6 +65,7 @@ #include "parser/parse_expr.h" #include "parser/parse_func.h" #include "parser/parse_type.h" +#include "rewrite/rewriteHandler.h" #include "utils/builtins.h" #include "utils/fmgroids.h" #include "utils/inval.h" @@ -144,6 +145,7 @@ static void AlterTypeRecurse(Oid typeOid, bool isImplicitArray, AlterTypeRecurseParams *atparams); +static bool ValidateDomainNeedGeneratedExprs(RelToCheck *rtc); /* * DefineType * Registers a new base type. @@ -3112,6 +3114,28 @@ AlterDomainValidateConstraint(List *names, const char *constrName) return address; } +static bool +ValidateDomainNeedGeneratedExprs(RelToCheck *rtc) +{ + Relation testrel = rtc->rel; + TupleDesc tupdesc = RelationGetDescr(testrel); + + if (tupdesc->constr && tupdesc->constr->has_generated_virtual) + { + int i; + int attnum; + Form_pg_attribute attr; + for (i = 0; i < rtc->natts; i++) + { + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + return true; + } + } + return false; +} + /* * Verify that all columns currently using the domain are not null. */ @@ -3121,6 +3145,15 @@ validateDomainNotNullConstraint(Oid domainoid) List *rels; ListCell *rt; + /* + * for domain not null constraint over virtual generated column + * it maybe need it in below. + */ + EState *estate; + ExprContext *econtext; + estate = CreateExecutorState(); + econtext = GetPerTupleExprContext(estate); + /* Fetch relation list with attributes based on this domain */ /* ShareLock is sufficient to prevent concurrent data changes */ @@ -3134,6 +3167,39 @@ validateDomainNotNullConstraint(Oid domainoid) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + Form_pg_attribute attr; + ExprState **ri_GeneratedExprs = NULL; + bool need_GeneratedExprs = false; + int attnum; + + /* cacahe generated columns handling */ + need_GeneratedExprs = ValidateDomainNeedGeneratedExprs(rtc); + if (need_GeneratedExprs) + { + ri_GeneratedExprs = (ExprState **) palloc0(tupdesc->natts * sizeof(ExprState *)); + + for (int i = 0; i < rtc->natts; i++) + { + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + NullTest *nnulltest; + Expr *expr; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_column_default(testrel, attnum); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + expr = (Expr *) nnulltest; + ri_GeneratedExprs[attnum - 1] = ExecPrepareExpr(expr, estate); + } + } + } + /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3146,8 +3212,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); if (slot_attisnull(slot, attnum)) { @@ -3158,14 +3224,30 @@ validateDomainNotNullConstraint(Oid domainoid) * only executes in an ALTER DOMAIN command, the client * should already know which domain is in question. */ - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains null values", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) + ereport(ERROR, + (errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + else + { + Assert(need_GeneratedExprs); + econtext->ecxt_scantuple = slot; + Assert(ri_GeneratedExprs[attnum - 1] != NULL); + if (!ExecCheck(ri_GeneratedExprs[attnum - 1] , econtext)) + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } } } + + ResetExprContext(econtext); } ExecDropSingleTupleTableSlot(slot); table_endscan(scan); @@ -3174,6 +3256,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Close each rel after processing, but keep lock */ table_close(testrel, NoLock); } + + FreeExecutorState(estate); } /* @@ -3210,6 +3294,32 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + ExprState **ri_GeneratedExprs = NULL; + bool need_GeneratedExprs = false; + Form_pg_attribute attr; + int attnum; + + /* cacahe generated columns handling */ + need_GeneratedExprs = ValidateDomainNeedGeneratedExprs(rtc); + + if (need_GeneratedExprs) + { + ri_GeneratedExprs = (ExprState **) palloc0(tupdesc->natts * sizeof(ExprState *)); + for (int i = 0; i < rtc->natts; i++) + { + Expr *gen_defexpr; + + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + + /* Fetch the GENERATED AS expression tree */ + gen_defexpr = (Expr *) build_column_default(testrel, attnum); + if (gen_defexpr == NULL) + elog(ERROR, "no generation expression found for column number %d of table \"%s\"", + attnum, RelationGetRelationName(testrel)); + ri_GeneratedExprs[attnum - 1] = ExecPrepareExpr(gen_defexpr, estate); + } + } /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3222,37 +3332,75 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; Datum d; bool isNull; Datum conResult; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); - d = slot_getattr(slot, attnum, &isNull); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); - econtext->domainValue_datum = d; - econtext->domainValue_isNull = isNull; - - conResult = ExecEvalExprSwitchContext(exprstate, - econtext, - &isNull); - - if (!isNull && !DatumGetBool(conResult)) + /* + * we first actually compute the virtual generated column value + * then do the CoerceToDomainValue check. + */ + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { + Datum ret; + bool isnull; + + Assert(need_GeneratedExprs); + econtext = GetPerTupleExprContext(estate); + econtext->ecxt_scantuple = slot; + + ret = ExecEvalExprSwitchContext(ri_GeneratedExprs[attnum - 1], + econtext, + &isnull); /* - * In principle the auxiliary information for this error - * should be errdomainconstraint(), but errtablecol() - * seems considerably more useful in practice. Since this - * code only executes in an ALTER DOMAIN command, the - * client should already know which domain is in question, - * and which constraint too. + * we probally don't need datumCopy to copy ret, since here + * we just check the value. */ - ereport(ERROR, - (errcode(ERRCODE_CHECK_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + econtext->domainValue_datum = ret; + econtext->domainValue_isNull = isnull; + econtext->ecxt_scantuple = NULL; + + conResult = ExecEvalExprSwitchContext(exprstate, + econtext, + &isNull); + if (!isNull && !DatumGetBool(conResult)) + ereport(ERROR, + errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } + else + { + d = slot_getattr(slot, attnum, &isNull); + + econtext->domainValue_datum = d; + econtext->domainValue_isNull = isNull; + + conResult = ExecEvalExprSwitchContext(exprstate, + econtext, + &isNull); + + if (!isNull && !DatumGetBool(conResult)) + { + /* + * In principle the auxiliary information for this error + * should be errdomainconstraint(), but errtablecol() + * seems considerably more useful in practice. Since this + * code only executes in an ALTER DOMAIN command, the + * client should already know which domain is in question, + * and which constraint too. + */ + ereport(ERROR, + (errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + } } } diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 53755ccdbad..e83e57bea0a 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -67,6 +67,7 @@ #include "storage/lmgr.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/lsyscache.h" #include "utils/rel.h" #include "utils/snapmgr.h" @@ -395,7 +396,7 @@ ExecCheckTIDVisible(EState *estate, * * This fills the resultRelInfo's ri_GeneratedExprsI/ri_NumGeneratedNeededI or * ri_GeneratedExprsU/ri_NumGeneratedNeededU fields, depending on cmdtype. - * This is used only for stored generated columns. + * This is used for stored and virtual generated columns. * * If cmdType == CMD_UPDATE, the ri_extraUpdatedCols field is filled too. * This is used by both stored and virtual generated columns. @@ -477,6 +478,33 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); ri_NumGeneratedNeeded++; } + else + { + /* + * Virtual generated columns only need to be computed when the + * type is domain_with_constraint. However, + * domain_with_constraint can be the element type of a range, the + * element type of a composite, or the element type of an array. + * + * To determine whether the true base element type is + * domain_with_constraint, multiple lookup_type_cache calls seems + * doable. However, this would add a lot of code. + * So, simplified it: only if the type is TYPTYPE_BASE and it's + * not an array type, computation is not needed. + */ + Oid typelem = InvalidOid; + Oid atttypid = TupleDescAttr(tupdesc, i)->atttypid; + char att_typtype = get_typtype(atttypid); + + if (att_typtype == TYPTYPE_BASE) + typelem = get_element_type(atttypid); + + if (att_typtype != TYPTYPE_BASE || OidIsValid(typelem)) + { + ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); + ri_NumGeneratedNeeded++; + } + } /* If UPDATE, mark column in resultRelInfo->ri_extraUpdatedCols */ if (cmdtype == CMD_UPDATE) @@ -518,7 +546,9 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, /* * Compute generated columns for a tuple. - * we might support virtual generated column in future, currently not. + * Generally, we don't need compute virtual generated column, except for column + * type is domain with constraint. Since virtual generated column don't have + * storage, we don't need stored the computed value. */ void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, @@ -532,9 +562,11 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, MemoryContext oldContext; Datum *values; bool *nulls; + bool need_compute = false; /* We should not be called unless this is true */ - Assert(tupdesc->constr && tupdesc->constr->has_generated_stored); + Assert(tupdesc->constr); + Assert(tupdesc->constr->has_generated_stored || tupdesc->constr->has_generated_virtual); /* * Initialize the expressions if we didn't already, and check whether we @@ -553,7 +585,8 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, if (resultRelInfo->ri_GeneratedExprsI == NULL) ExecInitGenerated(resultRelInfo, estate, cmdtype); /* Early exit is impossible given the prior Assert */ - Assert(resultRelInfo->ri_NumGeneratedNeededI > 0); + if (resultRelInfo->ri_GeneratedExprsI != NULL) + Assert(resultRelInfo->ri_NumGeneratedNeededI > 0); ri_GeneratedExprs = resultRelInfo->ri_GeneratedExprsI; } @@ -565,30 +598,40 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, slot_getallattrs(slot); memcpy(nulls, slot->tts_isnull, sizeof(*nulls) * natts); + need_compute = (resultRelInfo->ri_NumGeneratedNeededI > 0 || + resultRelInfo->ri_NumGeneratedNeededU > 0); + for (int i = 0; i < natts; i++) { CompactAttribute *attr = TupleDescCompactAttr(tupdesc, i); - if (ri_GeneratedExprs[i]) + if (need_compute && ri_GeneratedExprs[i] ) { Datum val; bool isnull; - Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED); - econtext->ecxt_scantuple = slot; val = ExecEvalExpr(ri_GeneratedExprs[i], econtext, &isnull); - /* - * We must make a copy of val as we have no guarantees about where - * memory for a pass-by-reference Datum is located. - */ - if (!isnull) - val = datumCopy(val, attr->attbyval, attr->attlen); + if (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED) + { + /* + * We must make a copy of val as we have no guarantees about where + * memory for a pass-by-reference Datum is located. + */ + if (!isnull) + val = datumCopy(val, attr->attbyval, attr->attlen); - values[i] = val; - nulls[i] = isnull; + values[i] = val; + nulls[i] = isnull; + } + else + { + Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + values[i] = (Datum) 0; + nulls[i] = true; + } } else { @@ -910,7 +953,8 @@ ExecInsert(ModifyTableContext *context, * Compute stored generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -1037,7 +1081,8 @@ ExecInsert(ModifyTableContext *context, * Compute stored generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -2122,10 +2167,11 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, slot->tts_tableOid = RelationGetRelid(resultRelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_UPDATE); } diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 0eef3fcfff1..7c8bacf9232 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -785,16 +785,65 @@ ERROR: relation "gtest23p" does not exist --INSERT INTO gtest23q VALUES (1, 2); -- ok --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +UPDATE gtest24 SET a = 6; -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +COPY gtest24 FROM stdin; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +CONTEXT: COPY gtest24, line 1: "6" +SELECT * FROM gtest24; + a | b +---+--- + 4 | 8 + 3 | 6 + | +(3 rows) + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ERROR: column "c" of relation "gtest24" contains null values +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +ERROR: column "b" of table "gtest24" contains null values +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok +INSERT INTO gtest24 (a) VALUES (NULL); -- error +ERROR: domain gtestdomain1 does not allow null values CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +INSERT INTO gtest24r (a) VALUES (5); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check2" +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +ERROR: null value in column "c" of relation "gtest24v" violates not-null constraint +DETAIL: Failing row contains ({"a": [6, -1], "b": [6, 10]}, virtual, virtual). +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); CREATE TABLE gtest28 OF gtest_type (f1 WITH OPTIONS GENERATED ALWAYS AS (f2 *2) VIRTUAL); diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index 485e2a317fe..81f03cc4a92 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -439,14 +439,49 @@ CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +UPDATE gtest24 SET a = 6; -- error +COPY gtest24 FROM stdin; --error +6 +\. + +SELECT * FROM gtest24; + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok + +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok + +INSERT INTO gtest24 (a) VALUES (NULL); -- error + CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +INSERT INTO gtest24r (a) VALUES (5); -- error + +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); -- 2.34.1 [text/x-patch] v3-0002-rename-ExecComputeGenerated-to-ExecComputeGenerat.patch (5.2K, ../../CACJufxFT3+0iY6aj4GYqi1kOdgvKP3teXT-1RrYagxhJKfxRTw@mail.gmail.com/3-v3-0002-rename-ExecComputeGenerated-to-ExecComputeGenerat.patch) download | inline diff: From 7096ea7b53316117e8ac4a309e88c9f543a956df Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 6 Mar 2025 12:35:19 +0800 Subject: [PATCH v3 2/3] rename ExecComputeGenerated to ExecComputeGenerated to support virtual generated column over domain type, we actually need compute the virtual generated expression. we did it at ExecComputeGenerated for stored, we can use it for virtual. so do the rename. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/commands/copyfrom.c | 4 ++-- src/backend/executor/execReplication.c | 8 ++++---- src/backend/executor/nodeModifyTable.c | 20 ++++++++++---------- src/include/executor/nodeModifyTable.h | 5 ++--- 4 files changed, 18 insertions(+), 19 deletions(-) diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index bcf66f0adf8..7f1078dfe39 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1346,8 +1346,8 @@ CopyFrom(CopyFromState cstate) /* Compute stored generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, myslot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, myslot, + CMD_INSERT); /* * If the target is a plain table, check the constraints of diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c index 5cef54f00ed..fdc379e7a44 100644 --- a/src/backend/executor/execReplication.c +++ b/src/backend/executor/execReplication.c @@ -549,8 +549,8 @@ ExecSimpleRelationInsert(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* Check the constraints of the tuple */ if (rel->rd_att->constr) @@ -646,8 +646,8 @@ ExecSimpleRelationUpdate(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); /* Check the constraints of the tuple */ if (rel->rd_att->constr) diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index b0fe50075ad..53755ccdbad 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -517,12 +517,12 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, } /* - * Compute stored generated columns for a tuple + * Compute generated columns for a tuple. + * we might support virtual generated column in future, currently not. */ void -ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype) +ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot, CmdType cmdtype) { Relation rel = resultRelInfo->ri_RelationDesc; TupleDesc tupdesc = RelationGetDescr(rel); @@ -911,8 +911,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * If the FDW supports batching, and batching is requested, accumulate @@ -1038,8 +1038,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * Check any RLS WITH CHECK policies. @@ -2126,8 +2126,8 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); } /* diff --git a/src/include/executor/nodeModifyTable.h b/src/include/executor/nodeModifyTable.h index bf3b592e28f..de374c46d3c 100644 --- a/src/include/executor/nodeModifyTable.h +++ b/src/include/executor/nodeModifyTable.h @@ -19,9 +19,8 @@ extern void ExecInitGenerated(ResultRelInfo *resultRelInfo, EState *estate, CmdType cmdtype); -extern void ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype); +extern void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot,CmdType cmdtype); extern ModifyTableState *ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags); extern void ExecEndModifyTable(ModifyTableState *node); -- 2.34.1 [text/x-patch] v3-0001-not-null-for-virtual-generated-column.patch (31.1K, ../../CACJufxFT3+0iY6aj4GYqi1kOdgvKP3teXT-1RrYagxhJKfxRTw@mail.gmail.com/4-v3-0001-not-null-for-virtual-generated-column.patch) download | inline diff: From f1f455eb8bcaab05c9af090bf9cb979cc7af7746 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Sat, 8 Mar 2025 17:38:25 +0800 Subject: [PATCH v3 1/3] not null for virtual generated column now we can add not null constraint on virtual generated column. not null constraint on virtual generated column make sure evaulation of the expanded generated expression does not yield null. the virtual generated columns does not store value, the storage is null. we do support ALTER COLUMN SET EXPRESSION over not null virtual generated column. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 10 - src/backend/commands/indexcmds.c | 10 +- src/backend/commands/tablecmds.c | 68 +++++- src/backend/executor/execMain.c | 220 +++++++++++++----- src/backend/parser/parse_utilcmd.c | 14 -- src/include/executor/executor.h | 4 + src/include/nodes/execnodes.h | 2 + .../regress/expected/generated_virtual.out | 89 +++++-- src/test/regress/sql/generated_virtual.sql | 50 +++- 9 files changed, 348 insertions(+), 119 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index bd3554c0bfd..b807ab66668 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -2615,11 +2615,6 @@ AddRelationNewConstraints(Relation rel, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(cdef->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), colnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * If the column already has a not-null constraint, we don't want @@ -2935,11 +2930,6 @@ AddRelationNotNullConstraints(Relation rel, List *constraints, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(constr->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), attnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * A column can only have one not-null constraint, so discard any diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 32ff3ca9a28..e690487eb3e 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -1126,10 +1126,12 @@ DefineIndex(Oid tableId, if (TupleDescAttr(RelationGetDescr(rel), attno - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - stmt->isconstraint ? - errmsg("unique constraints on virtual generated columns are not supported") : - errmsg("indexes on virtual generated columns are not supported"))); + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + stmt->primary ? + errmsg("primary key on virtual generated columns are not supported") : + stmt->isconstraint ? + errmsg("unique constraints on virtual generated columns are not supported") : + errmsg("indexes on virtual generated columns are not supported")); } /* diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 59156a1c1f6..41efda3d338 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -6080,6 +6080,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) TupleDesc newTupDesc; bool needscan = false; List *notnull_attrs; + List *all_virtual_nns = NIL; int i; ListCell *l; EState *estate; @@ -6183,6 +6184,16 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) needscan = true; } + foreach_int(attn, notnull_attrs) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn); + + Assert(attr->attnotnull); + Assert(!attr->attisdropped); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + all_virtual_nns = lappend_int(all_virtual_nns, attr->attnum); + } + if (newrel || needscan) { ExprContext *econtext; @@ -6193,6 +6204,22 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) List *dropped_attrs = NIL; ListCell *lc; Snapshot snapshot; + ResultRelInfo *rInfo; + MemoryContext oldcontext; + + if (list_length(all_virtual_nns) > 0) + { + Assert(newTupDesc->constr->has_generated_virtual); + Assert(newTupDesc->constr->has_not_null); + oldcontext = MemoryContextSwitchTo(estate->es_query_cxt); + rInfo = makeNode(ResultRelInfo); + InitResultRelInfo(rInfo, + oldrel, + 0, /* dummy rangetable index */ + NULL, + estate->es_instrument); + MemoryContextSwitchTo(oldcontext); + } if (newrel) ereport(DEBUG1, @@ -6275,6 +6302,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) while (table_scan_getnextslot(scan, ForwardScanDirection, oldslot)) { TupleTableSlot *insertslot; + bool virtual_notnull_check = false; if (tab->rewrite > 0) { @@ -6366,6 +6394,14 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) { Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn); + /* virtual generated column not null constraint handled below */ + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + if (!virtual_notnull_check) + virtual_notnull_check = true; + continue; + } ereport(ERROR, (errcode(ERRCODE_NOT_NULL_VIOLATION), errmsg("column \"%s\" of relation \"%s\" contains null values", @@ -6375,6 +6411,27 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) } } + if (virtual_notnull_check) + { + int attnum = -1; + Assert(list_length(all_virtual_nns) > 0); + + attnum = ExecRelCheckGenVirtualNotNull(rInfo, insertslot, + estate, + all_virtual_nns); + if (attnum > 0) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attnum - 1); + + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of relation \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(oldrel)), + errtablecol(oldrel, attnum)); + } + } + foreach(l, tab->constraints) { NewConstraint *con = lfirst(l); @@ -7824,14 +7881,6 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName, errmsg("cannot alter system column \"%s\"", colName))); - /* TODO: see transformColumnDefinition() */ - if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", - colName, RelationGetRelationName(rel)))); - /* See if there's already a constraint */ tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum); if (HeapTupleIsValid(tuple)) @@ -8500,6 +8549,9 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName, errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", colName, RelationGetRelationName(rel)))); + if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL && attTup->attnotnull) + tab->verify_new_notnull = true; + /* * We need to prevent this because a change of expression could affect a * row filter and inject expressions that are not permitted in a row diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index 0493b7d5365..51fe8efc559 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -51,6 +51,7 @@ #include "foreign/fdwapi.h" #include "mb/pg_wchar.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/queryjumble.h" #include "parser/parse_relation.h" #include "pgstat.h" @@ -1372,6 +1373,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo, resultRelInfo->ri_FdwState = NULL; resultRelInfo->ri_usesFdwDirectModify = false; resultRelInfo->ri_ConstraintExprs = NULL; + resultRelInfo->ri_GeneratedNotNullExprs = NULL; resultRelInfo->ri_GeneratedExprsI = NULL; resultRelInfo->ri_GeneratedExprsU = NULL; resultRelInfo->ri_projectReturning = NULL; @@ -1841,6 +1843,70 @@ ExecutePlan(QueryDesc *queryDesc, } +/* + * we warp "virtual_generated col IS NOT NULL" to a NullTest node. + * NullTest->arg is the virtual generated expression. return value of -1 means + * ok. return value > 0 means not null violation happended for that attribute + * number. + * all_virtual_nns is *all* the virtual generated column not-null attribute numbers. + * +*/ +int +ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, List *all_virtual_nns) +{ + Relation rel = resultRelInfo->ri_RelationDesc; + ExprContext *econtext; + MemoryContext oldContext; + int i = 0; + int cnt = list_length(all_virtual_nns); + + if (resultRelInfo->ri_GeneratedNotNullExprs == NULL) + { + oldContext = MemoryContextSwitchTo(estate->es_query_cxt); + resultRelInfo->ri_GeneratedNotNullExprs = + (ExprState **) palloc0(cnt * sizeof(ExprState *)); + + foreach_int(attidx, all_virtual_nns) + { + Expr *expr; + NullTest *nnulltest; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_generation_expression(rel, attidx); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + expr = (Expr *) nnulltest; + resultRelInfo->ri_GeneratedNotNullExprs[i++] = ExecPrepareExpr(expr, estate); + } + MemoryContextSwitchTo(oldContext); + } + + /* + * We will use the EState's per-tuple context for evaluating virtual + * generated column not null constraint expressions (creating it if it's not + * already there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + /* And evaluate the check constraints for virtual generated column */ + i = 0; + foreach_int(attnum, all_virtual_nns) + { + ExprState *exprstate = resultRelInfo->ri_GeneratedNotNullExprs[i++]; + if (exprstate && !ExecCheck(exprstate, econtext)) + return attnum; + } + + /* -1 result means no error */ + return -1; +} + /* * ExecRelCheck --- check that tuple meets constraints for result relation * @@ -2039,6 +2105,70 @@ ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, errtable(resultRelInfo->ri_RelationDesc))); } +/* not null constraint violation happened, now format the error message */ +static void +NotNullViolationErrorReport(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, int attrChk) +{ + Bitmapset *modifiedCols; + char *val_desc; + + Relation rel = resultRelInfo->ri_RelationDesc; + Relation orig_rel = rel; + + TupleDesc tupdesc = RelationGetDescr(rel); + TupleDesc orig_tupdesc = RelationGetDescr(rel); + Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + + Assert(attrChk > 0); + + /* + * If the tuple has been routed, it's been converted to the + * partition's rowtype, which might differ from the root + * table's. We must convert it back to the root table's + * rowtype so that val_desc shown error message matches the + * input tuple. + */ + if (resultRelInfo->ri_RootResultRelInfo) + { + ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; + AttrMap *map; + + tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); + /* a reverse map */ + map = build_attrmap_by_name_if_req(orig_tupdesc, + tupdesc, + false); + + /* + * Partition-specific slot's tupdesc can't be changed, so + * allocate a new one. + */ + if (map != NULL) + slot = execute_attr_map_slot(map, slot, + MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); + modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), + ExecGetUpdatedCols(rootrel, estate)); + rel = rootrel->ri_RelationDesc; + } + else + modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), + ExecGetUpdatedCols(resultRelInfo, estate)); + + val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), + slot, + tupdesc, + modifiedCols, + 64); + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", + NameStr(att->attname), + RelationGetRelationName(orig_rel)), + val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, + errtablecol(orig_rel, attrChk)); +} + /* * ExecConstraints - check constraints of the tuple in 'slot' * @@ -2058,73 +2188,57 @@ ExecConstraints(ResultRelInfo *resultRelInfo, TupleDesc tupdesc = RelationGetDescr(rel); TupleConstr *constr = tupdesc->constr; Bitmapset *modifiedCols; + Form_pg_attribute att; + int natts; + int attnum; + List *all_virtual_nns = NIL; + bool virtual_notnull_check = false; Assert(constr); /* we should not be called otherwise */ + natts = tupdesc->natts; if (constr->has_not_null) { - int natts = tupdesc->natts; - int attrChk; - - for (attrChk = 1; attrChk <= natts; attrChk++) + for (attnum = 1; attnum <= natts; attnum++) { - Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + att = TupleDescAttr(tupdesc, attnum - 1); - if (att->attnotnull && slot_attisnull(slot, attrChk)) + if (att->attnotnull && att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + all_virtual_nns = lappend_int(all_virtual_nns, att->attnum); + + if (att->attnotnull && slot_attisnull(slot, attnum)) { - char *val_desc; - Relation orig_rel = rel; - TupleDesc orig_tupdesc = RelationGetDescr(rel); - - /* - * If the tuple has been routed, it's been converted to the - * partition's rowtype, which might differ from the root - * table's. We must convert it back to the root table's - * rowtype so that val_desc shown error message matches the - * input tuple. - */ - if (resultRelInfo->ri_RootResultRelInfo) + if (att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { - ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; - AttrMap *map; - - tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); - /* a reverse map */ - map = build_attrmap_by_name_if_req(orig_tupdesc, - tupdesc, - false); - - /* - * Partition-specific slot's tupdesc can't be changed, so - * allocate a new one. - */ - if (map != NULL) - slot = execute_attr_map_slot(map, slot, - MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); - modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), - ExecGetUpdatedCols(rootrel, estate)); - rel = rootrel->ri_RelationDesc; + if (!virtual_notnull_check) + virtual_notnull_check = true; + continue; } - else - modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), - ExecGetUpdatedCols(resultRelInfo, estate)); - val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), - slot, - tupdesc, - modifiedCols, - 64); - - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", - NameStr(att->attname), - RelationGetRelationName(orig_rel)), - val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, - errtablecol(orig_rel, attrChk))); + NotNullViolationErrorReport(resultRelInfo, slot, estate, attnum); } } } + /* check virtual generated column not null constraint */ + if (virtual_notnull_check) + { + Assert(constr->has_not_null); + Assert(constr->has_generated_virtual); + Assert(list_length(all_virtual_nns) > 0); + + attnum = -1; + attnum = ExecRelCheckGenVirtualNotNull(resultRelInfo, slot, estate, all_virtual_nns); + + /* constraint evaulation return falsem do error report, also make an Assert */ + if (attnum > 0) + { + att = TupleDescAttr(tupdesc, attnum - 1); + Assert(att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + + NotNullViolationErrorReport(resultRelInfo, slot, estate, att->attnum); + } + } + if (rel->rd_rel->relchecks > 0) { const char *failed; diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index abbe1bb45a3..7e9a5f7411b 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -988,20 +988,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); - - /* - * TODO: Straightforward not-null constraints won't work on virtual - * generated columns, because there is no support for expanding the - * column when the constraint is checked. Maybe we could convert the - * not-null constraint into a full check constraint, so that the - * generation expression can be expanded at check time. - */ - if (column->is_not_null && column->generated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - parser_errposition(cxt->pstate, - constraint->location))); } /* diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index d12e3f451d2..30edc1cd644 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -220,6 +220,10 @@ extern ResultRelInfo *ExecGetTriggerResultRel(EState *estate, Oid relid, extern List *ExecGetAncestorResultRels(EState *estate, ResultRelInfo *resultRelInfo); extern void ExecConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate); +extern int ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, + TupleTableSlot *slot, + EState *estate, + List *all_virtual_nns); extern bool ExecPartitionCheck(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate, bool emitError); extern void ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index a323fa98bbb..1c72243468c 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -549,6 +549,8 @@ typedef struct ResultRelInfo /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_GeneratedNotNullExprs; /* * Arrays of stored generated columns ExprStates for INSERT/UPDATE/MERGE. */ diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 7ef05f45be7..0eef3fcfff1 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -664,28 +664,68 @@ INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails ERROR: new row for relation "gtest20c" violates check constraint "whole_row_check" DETAIL: Failing row contains (null, virtual). --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); -ERROR: not-null constraints are not supported on virtual generated columns -LINE 1: ... b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); - ^ ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21a" violates not-null constraint +DETAIL: Failing row contains (0, virtual). -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error -ERROR: not-null constraints are not supported on virtual generated columns +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +ERROR: column "b" of relation "gtest21ax" contains null values +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error -ERROR: not-null constraints are not supported on virtual generated columns +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; -ERROR: not-null constraints are not supported on virtual generated columns -DETAIL: Column "b" of relation "gtest21b" is a virtual generated column. ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21b (a) VALUES (NULL); -- error +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (null, virtual). ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (1, 2, virtual). +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (2, 10, virtual). +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +ERROR: column "f3" of relation "gtestnn_child" contains null values +INSERT INTO gtestnn_parent VALUES (10, 11, default); --error +select * from gtestnn_parent; + f1 | f2 | f3 +----+----+---- + 2 | 2 | 4 + 3 | 5 | 8 + 14 | 12 | 26 + 10 | 11 | 21 +(4 rows) + +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_childdef" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_child" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); ERROR: unique constraints on virtual generated columns are not supported @@ -693,7 +733,7 @@ ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22a VALUES (3); --INSERT INTO gtest22a VALUES (4); CREATE TABLE gtest22b (a int, b int GENERATED ALWAYS AS (a / 2) VIRTUAL, PRIMARY KEY (a, b)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary key on virtual generated columns are not supported --INSERT INTO gtest22b VALUES (2); --INSERT INTO gtest22b VALUES (2); -- indexes @@ -738,7 +778,7 @@ ERROR: foreign key constraints on virtual generated columns are not supported --DROP TABLE gtest23b; --DROP TABLE gtest23a; CREATE TABLE gtest23p (x int, y int GENERATED ALWAYS AS (x * 2) VIRTUAL, PRIMARY KEY (y)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary key on virtual generated columns are not supported --INSERT INTO gtest23p VALUES (1), (2), (3); CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); ERROR: relation "gtest23p" does not exist @@ -1029,7 +1069,7 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ERROR: cannot alter type of a column used by a generated column DETAIL: Column "a" is used by generated column "x". @@ -1047,7 +1087,8 @@ SELECT * FROM gtest27; ---+----+---- 3 | 7 | 20 4 | 11 | 30 -(2 rows) + | | +(3 rows) ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ERROR: cannot specify USING when altering type of generated column @@ -1056,6 +1097,14 @@ LINE 1: ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0... DETAIL: Column "x" is a generated column. ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error ERROR: column "x" of relation "gtest27" is a generated column +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +ERROR: column "x" of relation "gtest27" contains null values +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index dab8c92ef99..485e2a317fe 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -335,23 +335,46 @@ ALTER TABLE gtest20c ADD CONSTRAINT whole_row_check CHECK (gtest20c IS NOT NULL) INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +DROP TABLE gtest21ax; + CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (NULL); -- error ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now + +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +INSERT INTO gtestnn_parent VALUES (10, 11, default); --error +select * from gtestnn_parent; +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); @@ -524,13 +547,20 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ALTER TABLE gtest27 ALTER COLUMN x TYPE numeric; \d gtest27 SELECT * FROM gtest27; ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-13 12:22 jian he <[email protected]> parent: jian he <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: jian he @ 2025-03-13 12:22 UTC (permalink / raw) To: Xuneng Zhou <[email protected]>; +Cc: Navneet Kumar <[email protected]>; [email protected] hi. new patch attached. 0001 for virtual generated columns not null. minor change to fix the compiler warning. 0002-0004 is for domain over virtual generated columns. 0002: we need to compute the generation expression for the domain with constraints, thus rename ExecComputeStoredGenerated to ExecComputeGenerated. 0003. preparatory patch for 0004. soft error variant of ExecPrepareExpr, ExecInitExpr. for soft error processing of CoerceToDomain. see below description. 0004. no table rewrite for adding virtual generation column over domain with constraints. (syntax: ALTER TABLE xx ADD COLUMN X domain_type GENERATED ALWAYS AS (expression) VIRTUAL in phase3, ATRewriteTable: we already initialized AlteredTableInfo->newvals via ``ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL);`` we can easily evaluate it via ExecCheck. if fail, then error out. -------------- reason for the 0003 patch: ALTER DOMAIN ADD CONSTRAINT. since the virtual generated column has no actual storage. so, in validateDomainCheckConstraint we cannot use ``` d = slot_getattr(slot, attnum, &isNull); econtext->domainValue_datum = d; econtext->domainValue_isNull = isNull; conResult = ExecEvalExprSwitchContext(exprstate, econtext, &isNull); ``` to check whether existing generation expression satisfy the newly added domain constraint or not. we also need to evaluate error softly, because ALTER DOMAIN ADD CONSTRAINT need check exists table domain value satisfy the newly constraint or not. if we not do soft error evaluation, the error message would be like: ``value for domain gtestdomain1 violates check constraint "gtestdomain1_check"`` but we want error message like: ERROR: column "b" of table "gtest24" contains values that violate the new constraint -------------- Attachments: [text/x-patch] v4-0002-rename-ExecComputeStoredGenerated-to-ExecComputeG.patch (5.2K, ../../CACJufxHT4R1oABzeQuvjb6DHrig7k-QSr6LEe53Q_nLi9pfanA@mail.gmail.com/2-v4-0002-rename-ExecComputeStoredGenerated-to-ExecComputeG.patch) download | inline diff: From 30485418e6cd2dd993094b351b6ad10b4d885da3 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 13 Mar 2025 20:15:46 +0800 Subject: [PATCH v4 2/4] rename ExecComputeStoredGenerated to ExecComputeGenerated to support virtual generated column over domain type, we actually need compute the virtual generated expression. we did it at ExecComputeGenerated for stored, we can use it for virtual. so do the rename. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/commands/copyfrom.c | 4 ++-- src/backend/executor/execReplication.c | 8 ++++---- src/backend/executor/nodeModifyTable.c | 20 ++++++++++---------- src/include/executor/nodeModifyTable.h | 5 ++--- 4 files changed, 18 insertions(+), 19 deletions(-) diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index bcf66f0adf8..7f1078dfe39 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1346,8 +1346,8 @@ CopyFrom(CopyFromState cstate) /* Compute stored generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, myslot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, myslot, + CMD_INSERT); /* * If the target is a plain table, check the constraints of diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c index 0a9b880d250..05931bb3391 100644 --- a/src/backend/executor/execReplication.c +++ b/src/backend/executor/execReplication.c @@ -549,8 +549,8 @@ ExecSimpleRelationInsert(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* Check the constraints of the tuple */ if (rel->rd_att->constr) @@ -646,8 +646,8 @@ ExecSimpleRelationUpdate(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); /* Check the constraints of the tuple */ if (rel->rd_att->constr) diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index b0fe50075ad..53755ccdbad 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -517,12 +517,12 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, } /* - * Compute stored generated columns for a tuple + * Compute generated columns for a tuple. + * we might support virtual generated column in future, currently not. */ void -ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype) +ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot, CmdType cmdtype) { Relation rel = resultRelInfo->ri_RelationDesc; TupleDesc tupdesc = RelationGetDescr(rel); @@ -911,8 +911,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * If the FDW supports batching, and batching is requested, accumulate @@ -1038,8 +1038,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * Check any RLS WITH CHECK policies. @@ -2126,8 +2126,8 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); } /* diff --git a/src/include/executor/nodeModifyTable.h b/src/include/executor/nodeModifyTable.h index bf3b592e28f..de374c46d3c 100644 --- a/src/include/executor/nodeModifyTable.h +++ b/src/include/executor/nodeModifyTable.h @@ -19,9 +19,8 @@ extern void ExecInitGenerated(ResultRelInfo *resultRelInfo, EState *estate, CmdType cmdtype); -extern void ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype); +extern void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot,CmdType cmdtype); extern ModifyTableState *ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags); extern void ExecEndModifyTable(ModifyTableState *node); -- 2.34.1 [text/x-patch] v4-0004-domain-over-virtual-generated-column.patch (31.0K, ../../CACJufxHT4R1oABzeQuvjb6DHrig7k-QSr6LEe53Q_nLi9pfanA@mail.gmail.com/3-v4-0004-domain-over-virtual-generated-column.patch) download | inline diff: From 9e9b4cbf32bb5599a34803b7d12bad1dcb1ad03a Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 13 Mar 2025 20:18:32 +0800 Subject: [PATCH v4 4/4] domain over virtual generated column. domains that don't have constraints work just fine. domain constraints check happen within ExecComputeGenerated. we compute the virtual generated column in ExecComputeGenerated and discarded the value. domain_with_constaint can be element type of range, multirange, array, composite. to be bulletproof, if this column type is not type of TYPTYPE_BASE or it's an array type, then we do actually compute the generated expression. This can be have negative performance for INSERTs The following two query shows in pg_catalog, most of the system type is TYPTYPE_BASE. So I guess this compromise is fine. select count(*),typtype from pg_type where typnamespace = 11 group by 2; select typname, typrelid, pc.reltype, pc.oid, pt.oid from pg_type pt join pg_class pc on pc.oid = pt.typrelid where pt.typnamespace = 11 and pt.typtype = 'c' and pc.reltype = 0; ALTER DOMAIN ADD CONSTRAINT variant is supported. DOMAIN with default values are supported. but virtual generated column already have generated expression, so domain default expression doesn't matter. ALTER TABLE ADD VIRTUAL GENERATED COLUMN. need table scan to verify new column generation expression value satisfied the domain constraints. but no need table rewrite! discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 11 - src/backend/commands/copyfrom.c | 5 +- src/backend/commands/tablecmds.c | 41 +++- src/backend/commands/typecmds.c | 197 +++++++++++++++--- src/backend/executor/nodeModifyTable.c | 90 ++++++-- src/test/regress/expected/fast_default.out | 4 + .../regress/expected/generated_virtual.out | 65 +++++- src/test/regress/sql/fast_default.sql | 4 + src/test/regress/sql/generated_virtual.sql | 47 ++++- 9 files changed, 382 insertions(+), 82 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index b807ab66668..39e2ac38141 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -583,17 +583,6 @@ CheckAttributeType(const char *attname, } else if (att_typtype == TYPTYPE_DOMAIN) { - /* - * Prevent virtual generated columns from having a domain type. We - * would have to enforce domain constraints when columns underlying - * the generated column change. This could possibly be implemented, - * but it's not. - */ - if (flags & CHKATYPE_IS_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("virtual generated column \"%s\" cannot have a domain type", attname)); - /* * If it's a domain, recurse to check its base type. */ diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 7f1078dfe39..b8c984e1ec2 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1343,9 +1343,10 @@ CopyFrom(CopyFromState cstate) } else { - /* Compute stored generated columns */ + /* Compute generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && - resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) + (resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored || + resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, myslot, CMD_INSERT); diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index b8d82ba2809..5fe6f09e248 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -5980,7 +5980,7 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode, * rebuild data. */ if (tab->constraints != NIL || tab->verify_new_notnull || - tab->partition_constraint != NULL) + tab->newvals || tab->partition_constraint != NULL) ATRewriteTable(tab, InvalidOid); /* @@ -6100,6 +6100,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) BulkInsertState bistate; int ti_options; ExprState *partqualstate = NULL; + List *virtual_check = NIL; /* * Open the relation(s). We have surely already locked the existing @@ -6175,6 +6176,16 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) /* expr already planned */ ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL); + if (tab->rewrite == 0 && ex->is_generated) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, ex->attnum - 1); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL && + DomainHasConstraints(attr->atttypid)) + { + Assert(!attr->attisdropped); + virtual_check = lappend_int(virtual_check, attr->attnum); + } + } } notnull_attrs = NIL; @@ -6206,6 +6217,13 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) all_virtual_nns = lappend_int(all_virtual_nns, attr->attnum); } + /* + * We need to verify that domain constraints on the virtual generated column + * are satisfied, which requires table scan. + */ + if (virtual_check != NIL) + needscan = true; + if (newrel || needscan) { ExprContext *econtext; @@ -6469,6 +6487,27 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) } } + if (virtual_check != NIL) + { + foreach(l, tab->newvals) + { + NewColumnValue *ex = lfirst(l); + + if (!ex->is_generated) + continue; + + if(list_member_int(virtual_check, ex->attnum) && + !ExecCheck(ex->exprstate, econtext)) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, ex->attnum - 1); + ereport(ERROR, + errcode(ERRCODE_CHECK_VIOLATION), + errmsg("value for domain %s is violated by some row", + format_type_be(attr->atttypid))); + } + } + } + if (partqualstate && !ExecCheck(partqualstate, econtext)) { if (tab->validate_default) diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c index 3cb3ca1cca1..8f2888fe0e1 100644 --- a/src/backend/commands/typecmds.c +++ b/src/backend/commands/typecmds.c @@ -65,6 +65,7 @@ #include "parser/parse_expr.h" #include "parser/parse_func.h" #include "parser/parse_type.h" +#include "rewrite/rewriteHandler.h" #include "utils/builtins.h" #include "utils/fmgroids.h" #include "utils/inval.h" @@ -2772,6 +2773,8 @@ AlterDomainNotNull(List *names, bool notNull) typTup->typbasetype, typTup->typtypmod, constr, NameStr(typTup->typname), NULL); + CommandCounterIncrement(); + validateDomainNotNullConstraint(domainoid); } else @@ -2974,7 +2977,15 @@ AlterDomainAddConstraint(List *names, Node *newConstraint, * to. */ if (!constr->skip_validation) + { + /* + * validate virtual generated column over domain check constraint + * need see pg_constraint row + */ + CommandCounterIncrement(); + validateDomainCheckConstraint(domainoid, ccbin); + } /* * We must send out an sinval message for the domain, to ensure that @@ -3121,6 +3132,15 @@ validateDomainNotNullConstraint(Oid domainoid) List *rels; ListCell *rt; + /* + * EState is for domain not null constraint over virtual generated column. + * it maybe needed in below. + */ + EState *estate; + ExprContext *econtext; + estate = CreateExecutorState(); + econtext = GetPerTupleExprContext(estate); + /* Fetch relation list with attributes based on this domain */ /* ShareLock is sufficient to prevent concurrent data changes */ @@ -3134,6 +3154,44 @@ validateDomainNotNullConstraint(Oid domainoid) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + Form_pg_attribute attr; + ExprState **ri_GeneratedExprs = NULL; + int attnum; + int attr_virtual_generated = 0; + + /* cacahe virtual generated columns handling */ + if (tupdesc->constr && tupdesc->constr->has_generated_virtual) + { + ri_GeneratedExprs = (ExprState **) palloc0(tupdesc->natts * sizeof(ExprState *)); + + for (int i = 0; i < rtc->natts; i++) + { + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + NullTest *nnulltest; + Expr *expr; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_column_default(testrel, attnum); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + expr = (Expr *) nnulltest; + ri_GeneratedExprs[attnum - 1] = ExecPrepareExpr(expr, estate); + attr_virtual_generated++; + } + } + } + if (attr_virtual_generated == 0 && ri_GeneratedExprs != NULL) + { + pfree(ri_GeneratedExprs); + ri_GeneratedExprs = NULL; + } + /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3146,8 +3204,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); if (slot_attisnull(slot, attnum)) { @@ -3158,14 +3216,30 @@ validateDomainNotNullConstraint(Oid domainoid) * only executes in an ALTER DOMAIN command, the client * should already know which domain is in question. */ - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains null values", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) + ereport(ERROR, + (errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + else + { + econtext->ecxt_scantuple = slot; + Assert(ri_GeneratedExprs[attnum - 1] != NULL); + + if (!ExecCheck(ri_GeneratedExprs[attnum - 1] , econtext)) + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } } } + + ResetExprContext(econtext); } ExecDropSingleTupleTableSlot(slot); table_endscan(scan); @@ -3174,6 +3248,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Close each rel after processing, but keep lock */ table_close(testrel, NoLock); } + + FreeExecutorState(estate); } /* @@ -3210,6 +3286,39 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + ExprState **ri_GeneratedExprs = NULL; + Form_pg_attribute attr; + int attnum; + int attr_virtual_generated = 0; + + /* cacahe virtual generated columns handling */ + if (tupdesc->constr && tupdesc->constr->has_generated_virtual) + { + ri_GeneratedExprs = (ExprState **) palloc0(tupdesc->natts * sizeof(ExprState *)); + for (int i = 0; i < rtc->natts; i++) + { + Expr *gen_defexpr; + + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + gen_defexpr = (Expr *) build_column_default(testrel, attnum); + if (gen_defexpr == NULL) + elog(ERROR, "no generation expression found for column number %d of table \"%s\"", + attnum, RelationGetRelationName(testrel)); + + ri_GeneratedExprs[attnum - 1] = ExecPrepareExprSafe(gen_defexpr, estate); + attr_virtual_generated++; + } + } + } + if (attr_virtual_generated == 0 && ri_GeneratedExprs != NULL) + { + pfree(ri_GeneratedExprs); + ri_GeneratedExprs = NULL; + } + /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3222,37 +3331,63 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; Datum d; bool isNull; Datum conResult; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); - d = slot_getattr(slot, attnum, &isNull); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); - econtext->domainValue_datum = d; - econtext->domainValue_isNull = isNull; + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + econtext = GetPerTupleExprContext(estate); + econtext->ecxt_scantuple = slot; - conResult = ExecEvalExprSwitchContext(exprstate, - econtext, - &isNull); + Assert(ri_GeneratedExprs[attnum - 1]->escontext != NULL); + Assert(ri_GeneratedExprs != NULL); - if (!isNull && !DatumGetBool(conResult)) + conResult = ExecEvalExprSwitchContext(ri_GeneratedExprs[attnum - 1], + econtext, + &isNull); + if (SOFT_ERROR_OCCURRED(ri_GeneratedExprs[attnum - 1]->escontext)) + { + isNull = true; + ereport(ERROR, + errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } + } + else { - /* - * In principle the auxiliary information for this error - * should be errdomainconstraint(), but errtablecol() - * seems considerably more useful in practice. Since this - * code only executes in an ALTER DOMAIN command, the - * client should already know which domain is in question, - * and which constraint too. - */ - ereport(ERROR, - (errcode(ERRCODE_CHECK_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + d = slot_getattr(slot, attnum, &isNull); + + econtext->domainValue_datum = d; + econtext->domainValue_isNull = isNull; + + conResult = ExecEvalExprSwitchContext(exprstate, + econtext, + &isNull); + + if (!isNull && !DatumGetBool(conResult)) + { + /* + * In principle the auxiliary information for this error + * should be errdomainconstraint(), but errtablecol() + * seems considerably more useful in practice. Since this + * code only executes in an ALTER DOMAIN command, the + * client should already know which domain is in question, + * and which constraint too. + */ + ereport(ERROR, + (errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + } } } diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 53755ccdbad..152e2d7e357 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -67,6 +67,7 @@ #include "storage/lmgr.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/lsyscache.h" #include "utils/rel.h" #include "utils/snapmgr.h" @@ -395,7 +396,7 @@ ExecCheckTIDVisible(EState *estate, * * This fills the resultRelInfo's ri_GeneratedExprsI/ri_NumGeneratedNeededI or * ri_GeneratedExprsU/ri_NumGeneratedNeededU fields, depending on cmdtype. - * This is used only for stored generated columns. + * This is used for stored and virtual generated columns. * * If cmdType == CMD_UPDATE, the ri_extraUpdatedCols field is filled too. * This is used by both stored and virtual generated columns. @@ -477,6 +478,33 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); ri_NumGeneratedNeeded++; } + else + { + /* + * Virtual generated columns only need to be computed when the + * type is domain_with_constraint. However, + * domain_with_constraint can be the element type of a range, the + * element type of a composite, or the element type of an array. + * + * To determine whether the true base element type is + * domain_with_constraint, multiple lookup_type_cache calls seems + * doable. However, this would add a lot of code. + * So, simplified it: only if the type is TYPTYPE_BASE and it's + * not an array type, computation is not needed. + */ + Oid typelem = InvalidOid; + Oid atttypid = TupleDescAttr(tupdesc, i)->atttypid; + char att_typtype = get_typtype(atttypid); + + if (att_typtype == TYPTYPE_BASE) + typelem = get_element_type(atttypid); + + if (att_typtype != TYPTYPE_BASE || OidIsValid(typelem)) + { + ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); + ri_NumGeneratedNeeded++; + } + } /* If UPDATE, mark column in resultRelInfo->ri_extraUpdatedCols */ if (cmdtype == CMD_UPDATE) @@ -518,7 +546,9 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, /* * Compute generated columns for a tuple. - * we might support virtual generated column in future, currently not. + * Generally, we don't need compute virtual generated column, except for column + * type is domain with constraint. Since virtual generated column don't have + * storage, we don't need stored the computed value. */ void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, @@ -534,7 +564,8 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, bool *nulls; /* We should not be called unless this is true */ - Assert(tupdesc->constr && tupdesc->constr->has_generated_stored); + Assert(tupdesc->constr); + Assert(tupdesc->constr->has_generated_stored || tupdesc->constr->has_generated_virtual); /* * Initialize the expressions if we didn't already, and check whether we @@ -550,13 +581,20 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, } else { + /* + * we can exit earlier if the virtual generated column data type is not + * doamin with constraints. + */ if (resultRelInfo->ri_GeneratedExprsI == NULL) ExecInitGenerated(resultRelInfo, estate, cmdtype); - /* Early exit is impossible given the prior Assert */ - Assert(resultRelInfo->ri_NumGeneratedNeededI > 0); + if (resultRelInfo->ri_NumGeneratedNeededI == 0) + return; ri_GeneratedExprs = resultRelInfo->ri_GeneratedExprsI; } + if (ri_GeneratedExprs != NULL) + Assert(resultRelInfo->ri_NumGeneratedNeededU > 0 || resultRelInfo->ri_NumGeneratedNeededI > 0); + oldContext = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate)); values = palloc(sizeof(*values) * natts); @@ -574,21 +612,28 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, Datum val; bool isnull; - Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED); - econtext->ecxt_scantuple = slot; val = ExecEvalExpr(ri_GeneratedExprs[i], econtext, &isnull); - /* - * We must make a copy of val as we have no guarantees about where - * memory for a pass-by-reference Datum is located. - */ - if (!isnull) - val = datumCopy(val, attr->attbyval, attr->attlen); + if (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED) + { + /* + * We must make a copy of val as we have no guarantees about where + * memory for a pass-by-reference Datum is located. + */ + if (!isnull) + val = datumCopy(val, attr->attbyval, attr->attlen); - values[i] = val; - nulls[i] = isnull; + values[i] = val; + nulls[i] = isnull; + } + else + { + Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + values[i] = (Datum) 0; + nulls[i] = true; + } } else { @@ -907,10 +952,11 @@ ExecInsert(ModifyTableContext *context, slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -1034,10 +1080,11 @@ ExecInsert(ModifyTableContext *context, slot->tts_tableOid = RelationGetRelid(resultRelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -2122,10 +2169,11 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, slot->tts_tableOid = RelationGetRelid(resultRelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_UPDATE); } diff --git a/src/test/regress/expected/fast_default.out b/src/test/regress/expected/fast_default.out index ccbcdf8403f..e1353560aba 100644 --- a/src/test/regress/expected/fast_default.out +++ b/src/test/regress/expected/fast_default.out @@ -70,6 +70,9 @@ NOTICE: rewriting table has_volatile for reason 4 -- stored generated columns need a rewrite ALTER TABLE has_volatile ADD col7 int GENERATED ALWAYS AS (55) stored; NOTICE: rewriting table has_volatile for reason 2 +-- virtual generated columns over volatile domain constraint don't need a rewrite +CREATE DOMAIN d1 as INT CHECK(value < random(min=>12::int, max=>21)); +ALTER TABLE has_volatile ADD col8 int GENERATED ALWAYS AS (1 + id) VIRTUAL; -- Test a large sample of different datatypes CREATE TABLE T(pk INT NOT NULL PRIMARY KEY, c_int INT DEFAULT 1); SELECT set('t'); @@ -922,6 +925,7 @@ DROP FUNCTION set(name); DROP FUNCTION comp(); DROP TABLE m; DROP TABLE has_volatile; +DROP DOMAIN d1; DROP EVENT TRIGGER has_volatile_rewrite; DROP FUNCTION log_rewrite; DROP SCHEMA fast_default; diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 3b5723599f1..3ddcd1aba72 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -785,16 +785,63 @@ ERROR: relation "gtest23p" does not exist --INSERT INTO gtest23q VALUES (1, 2); -- ok --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +UPDATE gtest24 SET a = 6; -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +COPY gtest24 FROM stdin; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +CONTEXT: COPY gtest24, line 1: "6" +SELECT * FROM gtest24; + a | b +---+--- + 4 | 8 + 3 | 6 + | +(3 rows) + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ERROR: column "c" of relation "gtest24" contains null values +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +ERROR: column "b" of table "gtest24" contains null values +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +INSERT INTO gtest24r (a) VALUES (5); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check2" +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +ERROR: null value in column "c" of relation "gtest24v" violates not-null constraint +DETAIL: Failing row contains ({"a": [6, -1], "b": [6, 10]}, virtual, virtual). +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); CREATE TABLE gtest28 OF gtest_type (f1 WITH OPTIONS GENERATED ALWAYS AS (f2 *2) VIRTUAL); diff --git a/src/test/regress/sql/fast_default.sql b/src/test/regress/sql/fast_default.sql index 068dd0bc8aa..ffec1e11011 100644 --- a/src/test/regress/sql/fast_default.sql +++ b/src/test/regress/sql/fast_default.sql @@ -77,6 +77,9 @@ ALTER TABLE has_volatile ALTER COLUMN col1 SET DATA TYPE float8, -- stored generated columns need a rewrite ALTER TABLE has_volatile ADD col7 int GENERATED ALWAYS AS (55) stored; +-- virtual generated columns over volatile domain constraint don't need a rewrite +CREATE DOMAIN d1 as INT CHECK(value < random(min=>12::int, max=>21)); +ALTER TABLE has_volatile ADD col8 int GENERATED ALWAYS AS (1 + id) VIRTUAL; -- Test a large sample of different datatypes @@ -616,6 +619,7 @@ DROP FUNCTION set(name); DROP FUNCTION comp(); DROP TABLE m; DROP TABLE has_volatile; +DROP DOMAIN d1; DROP EVENT TRIGGER has_volatile_rewrite; DROP FUNCTION log_rewrite; DROP SCHEMA fast_default; diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index 485e2a317fe..73e507ae8e6 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -439,14 +439,47 @@ CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +UPDATE gtest24 SET a = 6; -- error +COPY gtest24 FROM stdin; --error +6 +\. + +SELECT * FROM gtest24; + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok + +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok + CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +INSERT INTO gtest24r (a) VALUES (5); -- error + +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); -- 2.34.1 [text/x-patch] v4-0003-soft-error-variant-of-ExecPrepareExpr-ExecInitExp.patch (3.9K, ../../CACJufxHT4R1oABzeQuvjb6DHrig7k-QSr6LEe53Q_nLi9pfanA@mail.gmail.com/4-v4-0003-soft-error-variant-of-ExecPrepareExpr-ExecInitExp.patch) download | inline diff: From 079526f201136c32be42774b8eec5c829ab728b2 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 13 Mar 2025 15:05:41 +0800 Subject: [PATCH v4 3/4] soft error variant of ExecPrepareExpr, ExecInitExpr ExecPrepareExprSafe and ExecInitExprSafe. ExecPrepareExprSafe initialize for expression execution with soft error support. not all expression node support it. some like CoerceToDomain do support it. XXX more comments. discussion: https://postgr.es/m/CACJufxE_+iZBR1i49k_AHigppPwLTJi6km8NOsC7FWvKdEmmXg@mail.gmail.com --- src/backend/executor/execExpr.c | 63 +++++++++++++++++++++++++++++++++ src/include/executor/executor.h | 2 ++ 2 files changed, 65 insertions(+) diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c index f1569879b52..b8f5f647281 100644 --- a/src/backend/executor/execExpr.c +++ b/src/backend/executor/execExpr.c @@ -170,6 +170,46 @@ ExecInitExpr(Expr *node, PlanState *parent) return state; } +/* + * ExecInitExpr: soft error variant of ExecInitExpr. + * use it only for expression nodes support soft errors, not all expression + * nodes support it. +*/ +ExprState * +ExecInitExprSafe(Expr *node, PlanState *parent) +{ + ExprState *state; + ExprEvalStep scratch = {0}; + + /* Special case: NULL expression produces a NULL ExprState pointer */ + if (node == NULL) + return NULL; + + /* Initialize ExprState with empty step list */ + state = makeNode(ExprState); + state->expr = node; + state->parent = parent; + state->ext_params = NULL; + state->escontext = makeNode(ErrorSaveContext); + state->escontext->type = T_ErrorSaveContext; + state->escontext->error_occurred = false; + state->escontext->details_wanted = true; + + /* Insert setup steps as needed */ + ExecCreateExprSetupSteps(state, (Node *) node); + + /* Compile the expression proper */ + ExecInitExprRec(node, state, &state->resvalue, &state->resnull); + + /* Finally, append a DONE step */ + scratch.opcode = EEOP_DONE_RETURN; + ExprEvalPushStep(state, &scratch); + + ExecReadyExpr(state); + + return state; +} + /* * ExecInitExprWithParams: prepare a standalone expression tree for execution * @@ -778,6 +818,29 @@ ExecPrepareExpr(Expr *node, EState *estate) return result; } +/* + * ExecPrepareExprSafe: soft error variant of ExecPrepareExpr. + * + * use it when expression node *support* soft error expression execution. + * ExecPrepareExpr comments apply to here too. + */ +ExprState * +ExecPrepareExprSafe(Expr *node, EState *estate) +{ + ExprState *result; + MemoryContext oldcontext; + + oldcontext = MemoryContextSwitchTo(estate->es_query_cxt); + + node = expression_planner(node); + + result = ExecInitExprSafe(node, NULL); + + MemoryContextSwitchTo(oldcontext); + + return result; +} + /* * ExecPrepareQual --- initialize for qual execution outside a normal * Plan tree context. diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index 4063ed68f5f..28e7df4f336 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -309,6 +309,7 @@ ExecProcNode(PlanState *node) * prototypes from functions in execExpr.c */ extern ExprState *ExecInitExpr(Expr *node, PlanState *parent); +extern ExprState *ExecInitExprSafe(Expr *node, PlanState *parent); extern ExprState *ExecInitExprWithParams(Expr *node, ParamListInfo ext_params); extern ExprState *ExecInitQual(List *qual, PlanState *parent); extern ExprState *ExecInitCheck(List *qual, PlanState *parent); @@ -357,6 +358,7 @@ extern ProjectionInfo *ExecBuildUpdateProjection(List *targetList, TupleTableSlot *slot, PlanState *parent); extern ExprState *ExecPrepareExpr(Expr *node, EState *estate); +extern ExprState *ExecPrepareExprSafe(Expr *node, EState *estate); extern ExprState *ExecPrepareQual(List *qual, EState *estate); extern ExprState *ExecPrepareCheck(List *qual, EState *estate); extern List *ExecPrepareExprList(List *nodes, EState *estate); -- 2.34.1 [text/x-patch] v4-0001-not-null-for-virtual-generated-column.patch (31.1K, ../../CACJufxHT4R1oABzeQuvjb6DHrig7k-QSr6LEe53Q_nLi9pfanA@mail.gmail.com/5-v4-0001-not-null-for-virtual-generated-column.patch) download | inline diff: From 3541711e18717dd5d2c93c7e2521249b01d6db7e Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Wed, 12 Mar 2025 22:07:57 +0800 Subject: [PATCH v4 1/4] not null for virtual generated column now we can add not null constraint on virtual generated column. not null constraint on virtual generated column make sure evaulation of the expanded generated expression does not yield null. the virtual generated columns does not store value, the storage is null. we do support ALTER COLUMN SET EXPRESSION over not null virtual generated column. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 10 - src/backend/commands/indexcmds.c | 10 +- src/backend/commands/tablecmds.c | 68 +++++- src/backend/executor/execMain.c | 220 +++++++++++++----- src/backend/parser/parse_utilcmd.c | 14 -- src/include/executor/executor.h | 4 + src/include/nodes/execnodes.h | 2 + .../regress/expected/generated_virtual.out | 89 +++++-- src/test/regress/sql/generated_virtual.sql | 50 +++- 9 files changed, 348 insertions(+), 119 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index bd3554c0bfd..b807ab66668 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -2615,11 +2615,6 @@ AddRelationNewConstraints(Relation rel, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(cdef->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), colnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * If the column already has a not-null constraint, we don't want @@ -2935,11 +2930,6 @@ AddRelationNotNullConstraints(Relation rel, List *constraints, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(constr->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), attnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * A column can only have one not-null constraint, so discard any diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 32ff3ca9a28..e690487eb3e 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -1126,10 +1126,12 @@ DefineIndex(Oid tableId, if (TupleDescAttr(RelationGetDescr(rel), attno - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - stmt->isconstraint ? - errmsg("unique constraints on virtual generated columns are not supported") : - errmsg("indexes on virtual generated columns are not supported"))); + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + stmt->primary ? + errmsg("primary key on virtual generated columns are not supported") : + stmt->isconstraint ? + errmsg("unique constraints on virtual generated columns are not supported") : + errmsg("indexes on virtual generated columns are not supported")); } /* diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 18ff8956577..b8d82ba2809 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -6092,6 +6092,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) TupleDesc newTupDesc; bool needscan = false; List *notnull_attrs; + List *all_virtual_nns = NIL; int i; ListCell *l; EState *estate; @@ -6195,6 +6196,16 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) needscan = true; } + foreach_int(attn, notnull_attrs) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn); + + Assert(attr->attnotnull); + Assert(!attr->attisdropped); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + all_virtual_nns = lappend_int(all_virtual_nns, attr->attnum); + } + if (newrel || needscan) { ExprContext *econtext; @@ -6205,6 +6216,22 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) List *dropped_attrs = NIL; ListCell *lc; Snapshot snapshot; + ResultRelInfo *rInfo = NULL; + MemoryContext oldcontext; + + if (list_length(all_virtual_nns) > 0) + { + Assert(newTupDesc->constr->has_generated_virtual); + Assert(newTupDesc->constr->has_not_null); + oldcontext = MemoryContextSwitchTo(estate->es_query_cxt); + rInfo = makeNode(ResultRelInfo); + InitResultRelInfo(rInfo, + oldrel, + 0, /* dummy rangetable index */ + NULL, + estate->es_instrument); + MemoryContextSwitchTo(oldcontext); + } if (newrel) ereport(DEBUG1, @@ -6287,6 +6314,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) while (table_scan_getnextslot(scan, ForwardScanDirection, oldslot)) { TupleTableSlot *insertslot; + bool virtual_notnull_check = false; if (tab->rewrite > 0) { @@ -6378,6 +6406,14 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) { Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn); + /* virtual generated column not null constraint handled below */ + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + if (!virtual_notnull_check) + virtual_notnull_check = true; + continue; + } ereport(ERROR, (errcode(ERRCODE_NOT_NULL_VIOLATION), errmsg("column \"%s\" of relation \"%s\" contains null values", @@ -6387,6 +6423,27 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) } } + if (virtual_notnull_check) + { + int attnum = -1; + Assert(list_length(all_virtual_nns) > 0); + + attnum = ExecRelCheckGenVirtualNotNull(rInfo, insertslot, + estate, + all_virtual_nns); + if (attnum > 0) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attnum - 1); + + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of relation \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(oldrel)), + errtablecol(oldrel, attnum)); + } + } + foreach(l, tab->constraints) { NewConstraint *con = lfirst(l); @@ -7836,14 +7893,6 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName, errmsg("cannot alter system column \"%s\"", colName))); - /* TODO: see transformColumnDefinition() */ - if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", - colName, RelationGetRelationName(rel)))); - /* See if there's already a constraint */ tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum); if (HeapTupleIsValid(tuple)) @@ -8512,6 +8561,9 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName, errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", colName, RelationGetRelationName(rel)))); + if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL && attTup->attnotnull) + tab->verify_new_notnull = true; + /* * We need to prevent this because a change of expression could affect a * row filter and inject expressions that are not permitted in a row diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index 0493b7d5365..51fe8efc559 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -51,6 +51,7 @@ #include "foreign/fdwapi.h" #include "mb/pg_wchar.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/queryjumble.h" #include "parser/parse_relation.h" #include "pgstat.h" @@ -1372,6 +1373,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo, resultRelInfo->ri_FdwState = NULL; resultRelInfo->ri_usesFdwDirectModify = false; resultRelInfo->ri_ConstraintExprs = NULL; + resultRelInfo->ri_GeneratedNotNullExprs = NULL; resultRelInfo->ri_GeneratedExprsI = NULL; resultRelInfo->ri_GeneratedExprsU = NULL; resultRelInfo->ri_projectReturning = NULL; @@ -1841,6 +1843,70 @@ ExecutePlan(QueryDesc *queryDesc, } +/* + * we warp "virtual_generated col IS NOT NULL" to a NullTest node. + * NullTest->arg is the virtual generated expression. return value of -1 means + * ok. return value > 0 means not null violation happended for that attribute + * number. + * all_virtual_nns is *all* the virtual generated column not-null attribute numbers. + * +*/ +int +ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, List *all_virtual_nns) +{ + Relation rel = resultRelInfo->ri_RelationDesc; + ExprContext *econtext; + MemoryContext oldContext; + int i = 0; + int cnt = list_length(all_virtual_nns); + + if (resultRelInfo->ri_GeneratedNotNullExprs == NULL) + { + oldContext = MemoryContextSwitchTo(estate->es_query_cxt); + resultRelInfo->ri_GeneratedNotNullExprs = + (ExprState **) palloc0(cnt * sizeof(ExprState *)); + + foreach_int(attidx, all_virtual_nns) + { + Expr *expr; + NullTest *nnulltest; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_generation_expression(rel, attidx); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + expr = (Expr *) nnulltest; + resultRelInfo->ri_GeneratedNotNullExprs[i++] = ExecPrepareExpr(expr, estate); + } + MemoryContextSwitchTo(oldContext); + } + + /* + * We will use the EState's per-tuple context for evaluating virtual + * generated column not null constraint expressions (creating it if it's not + * already there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + /* And evaluate the check constraints for virtual generated column */ + i = 0; + foreach_int(attnum, all_virtual_nns) + { + ExprState *exprstate = resultRelInfo->ri_GeneratedNotNullExprs[i++]; + if (exprstate && !ExecCheck(exprstate, econtext)) + return attnum; + } + + /* -1 result means no error */ + return -1; +} + /* * ExecRelCheck --- check that tuple meets constraints for result relation * @@ -2039,6 +2105,70 @@ ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, errtable(resultRelInfo->ri_RelationDesc))); } +/* not null constraint violation happened, now format the error message */ +static void +NotNullViolationErrorReport(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, int attrChk) +{ + Bitmapset *modifiedCols; + char *val_desc; + + Relation rel = resultRelInfo->ri_RelationDesc; + Relation orig_rel = rel; + + TupleDesc tupdesc = RelationGetDescr(rel); + TupleDesc orig_tupdesc = RelationGetDescr(rel); + Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + + Assert(attrChk > 0); + + /* + * If the tuple has been routed, it's been converted to the + * partition's rowtype, which might differ from the root + * table's. We must convert it back to the root table's + * rowtype so that val_desc shown error message matches the + * input tuple. + */ + if (resultRelInfo->ri_RootResultRelInfo) + { + ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; + AttrMap *map; + + tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); + /* a reverse map */ + map = build_attrmap_by_name_if_req(orig_tupdesc, + tupdesc, + false); + + /* + * Partition-specific slot's tupdesc can't be changed, so + * allocate a new one. + */ + if (map != NULL) + slot = execute_attr_map_slot(map, slot, + MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); + modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), + ExecGetUpdatedCols(rootrel, estate)); + rel = rootrel->ri_RelationDesc; + } + else + modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), + ExecGetUpdatedCols(resultRelInfo, estate)); + + val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), + slot, + tupdesc, + modifiedCols, + 64); + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", + NameStr(att->attname), + RelationGetRelationName(orig_rel)), + val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, + errtablecol(orig_rel, attrChk)); +} + /* * ExecConstraints - check constraints of the tuple in 'slot' * @@ -2058,73 +2188,57 @@ ExecConstraints(ResultRelInfo *resultRelInfo, TupleDesc tupdesc = RelationGetDescr(rel); TupleConstr *constr = tupdesc->constr; Bitmapset *modifiedCols; + Form_pg_attribute att; + int natts; + int attnum; + List *all_virtual_nns = NIL; + bool virtual_notnull_check = false; Assert(constr); /* we should not be called otherwise */ + natts = tupdesc->natts; if (constr->has_not_null) { - int natts = tupdesc->natts; - int attrChk; - - for (attrChk = 1; attrChk <= natts; attrChk++) + for (attnum = 1; attnum <= natts; attnum++) { - Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + att = TupleDescAttr(tupdesc, attnum - 1); - if (att->attnotnull && slot_attisnull(slot, attrChk)) + if (att->attnotnull && att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + all_virtual_nns = lappend_int(all_virtual_nns, att->attnum); + + if (att->attnotnull && slot_attisnull(slot, attnum)) { - char *val_desc; - Relation orig_rel = rel; - TupleDesc orig_tupdesc = RelationGetDescr(rel); - - /* - * If the tuple has been routed, it's been converted to the - * partition's rowtype, which might differ from the root - * table's. We must convert it back to the root table's - * rowtype so that val_desc shown error message matches the - * input tuple. - */ - if (resultRelInfo->ri_RootResultRelInfo) + if (att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { - ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; - AttrMap *map; - - tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); - /* a reverse map */ - map = build_attrmap_by_name_if_req(orig_tupdesc, - tupdesc, - false); - - /* - * Partition-specific slot's tupdesc can't be changed, so - * allocate a new one. - */ - if (map != NULL) - slot = execute_attr_map_slot(map, slot, - MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); - modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), - ExecGetUpdatedCols(rootrel, estate)); - rel = rootrel->ri_RelationDesc; + if (!virtual_notnull_check) + virtual_notnull_check = true; + continue; } - else - modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), - ExecGetUpdatedCols(resultRelInfo, estate)); - val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), - slot, - tupdesc, - modifiedCols, - 64); - - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", - NameStr(att->attname), - RelationGetRelationName(orig_rel)), - val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, - errtablecol(orig_rel, attrChk))); + NotNullViolationErrorReport(resultRelInfo, slot, estate, attnum); } } } + /* check virtual generated column not null constraint */ + if (virtual_notnull_check) + { + Assert(constr->has_not_null); + Assert(constr->has_generated_virtual); + Assert(list_length(all_virtual_nns) > 0); + + attnum = -1; + attnum = ExecRelCheckGenVirtualNotNull(resultRelInfo, slot, estate, all_virtual_nns); + + /* constraint evaulation return falsem do error report, also make an Assert */ + if (attnum > 0) + { + att = TupleDescAttr(tupdesc, attnum - 1); + Assert(att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + + NotNullViolationErrorReport(resultRelInfo, slot, estate, att->attnum); + } + } + if (rel->rd_rel->relchecks > 0) { const char *failed; diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index abbe1bb45a3..7e9a5f7411b 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -988,20 +988,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); - - /* - * TODO: Straightforward not-null constraints won't work on virtual - * generated columns, because there is no support for expanding the - * column when the constraint is checked. Maybe we could convert the - * not-null constraint into a full check constraint, so that the - * generation expression can be expanded at check time. - */ - if (column->is_not_null && column->generated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - parser_errposition(cxt->pstate, - constraint->location))); } /* diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index 0d2ffabda68..4063ed68f5f 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -220,6 +220,10 @@ extern ResultRelInfo *ExecGetTriggerResultRel(EState *estate, Oid relid, extern List *ExecGetAncestorResultRels(EState *estate, ResultRelInfo *resultRelInfo); extern void ExecConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate); +extern int ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, + TupleTableSlot *slot, + EState *estate, + List *all_virtual_nns); extern bool ExecPartitionCheck(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate, bool emitError); extern void ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 575b0b1bd24..36b4b497a2d 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -549,6 +549,8 @@ typedef struct ResultRelInfo /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_GeneratedNotNullExprs; /* * Arrays of stored generated columns ExprStates for INSERT/UPDATE/MERGE. */ diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index dc09c85938e..3b5723599f1 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -664,28 +664,68 @@ INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails ERROR: new row for relation "gtest20c" violates check constraint "whole_row_check" DETAIL: Failing row contains (null, virtual). --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); -ERROR: not-null constraints are not supported on virtual generated columns -LINE 1: ... b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); - ^ ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21a" violates not-null constraint +DETAIL: Failing row contains (0, virtual). -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error -ERROR: not-null constraints are not supported on virtual generated columns +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +ERROR: column "b" of relation "gtest21ax" contains null values +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error -ERROR: not-null constraints are not supported on virtual generated columns +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; -ERROR: not-null constraints are not supported on virtual generated columns -DETAIL: Column "b" of relation "gtest21b" is a virtual generated column. ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21b (a) VALUES (NULL); -- error +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (null, virtual). ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (1, 2, virtual). +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (2, 10, virtual). +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +ERROR: column "f3" of relation "gtestnn_child" contains null values +INSERT INTO gtestnn_parent VALUES (10, 11, default); --error +select * from gtestnn_parent; + f1 | f2 | f3 +----+----+---- + 2 | 2 | 4 + 3 | 5 | 8 + 14 | 12 | 26 + 10 | 11 | 21 +(4 rows) + +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_childdef" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_child" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); ERROR: unique constraints on virtual generated columns are not supported @@ -693,7 +733,7 @@ ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22a VALUES (3); --INSERT INTO gtest22a VALUES (4); CREATE TABLE gtest22b (a int, b int GENERATED ALWAYS AS (a / 2) VIRTUAL, PRIMARY KEY (a, b)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary key on virtual generated columns are not supported --INSERT INTO gtest22b VALUES (2); --INSERT INTO gtest22b VALUES (2); -- indexes @@ -738,7 +778,7 @@ ERROR: foreign key constraints on virtual generated columns are not supported --DROP TABLE gtest23b; --DROP TABLE gtest23a; CREATE TABLE gtest23p (x int, y int GENERATED ALWAYS AS (x * 2) VIRTUAL, PRIMARY KEY (y)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary key on virtual generated columns are not supported --INSERT INTO gtest23p VALUES (1), (2), (3); CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); ERROR: relation "gtest23p" does not exist @@ -1029,7 +1069,7 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ERROR: cannot alter type of a column used by a generated column DETAIL: Column "a" is used by generated column "x". @@ -1047,7 +1087,8 @@ SELECT * FROM gtest27; ---+----+---- 3 | 7 | 20 4 | 11 | 30 -(2 rows) + | | +(3 rows) ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ERROR: cannot specify USING when altering type of generated column @@ -1056,6 +1097,14 @@ LINE 1: ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0... DETAIL: Column "x" is a generated column. ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error ERROR: column "x" of relation "gtest27" is a generated column +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +ERROR: column "x" of relation "gtest27" contains null values +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index dab8c92ef99..485e2a317fe 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -335,23 +335,46 @@ ALTER TABLE gtest20c ADD CONSTRAINT whole_row_check CHECK (gtest20c IS NOT NULL) INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +DROP TABLE gtest21ax; + CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (NULL); -- error ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now + +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +INSERT INTO gtestnn_parent VALUES (10, 11, default); --error +select * from gtestnn_parent; +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); @@ -524,13 +547,20 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ALTER TABLE gtest27 ALTER COLUMN x TYPE numeric; \d gtest27 SELECT * FROM gtest27; ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-19 16:19 Álvaro Herrera <[email protected]> parent: jian he <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: Álvaro Herrera @ 2025-03-19 16:19 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: Xuneng Zhou <[email protected]>; Navneet Kumar <[email protected]>; [email protected] On 2025-Mar-13, jian he wrote: > hi. > > new patch attached. > > 0001 for virtual generated columns not null. > minor change to fix the compiler warning. I gave a look at 0001, and I propose some fixes. 0001 is just a typo in an error message. 0002 is pgindent. Then 0003 contain some more interesting bits: - in ExecRelCheckGenVirtualNotNull() it seems more natural to an AttrNumber rather than int, and use the InvalidAttrNumber value rather than -1 to indicate that all columns are ok. Also, use foreach_current_index instead of manually counting the loop. - ATRewriteTable can be simplified if we no longer add the virtual generated columns with not nulls to the notnulls_attrs list, but instead we store the attnums in a separate list. That way, the machinery around ExecRelCheckGenVirtualNotNull made less convoluted. - in ExecConstraints, you removed a comment (which ended up in NotNullViolationErrorReport), which was OK as far as that went; but there was another comment a few lines below which said "See the comment above", which no longer made sense. To fix it, I duplicated the original comment in the place where "See the..." comment was. - renamed NotNullViolationErrorReport to ReportNotNullViolationError. Perhaps a better name is still possible -- something in line with ExecPartitionCheckEmitError? (However, that function is exported, while the new one is not. So we probably don't need an "Exec" prefix for it. I don't particularly like that name very much anyway.) - Reduce scope of variables all over the place. - Added a bunch more comments. Other comments: * The block in ATRewriteTable that creates a resultRelInfo for ExecRelCheckGenVirtualNotNull needs an explanation. * I suspect the locations for the new functions were selected with the help of a dartboard. ExecRelCheckGenVirtualNotNull() in particular looks like it could use a better location. Maybe it's better right after ExecConstraints, and ReportNotNullViolationError (or whatever we name it) can go after it. * I don't find the name all_virtual_nns particularly appropriate. Maybe virtual_notnull_attrs? * There are some funny rules around nulls on rowtypes. I think allowing this tuple is wrong (and I left an XXX comment near where the 'argisrow' flag is set): create type twoints as (a int, b int); create table foo (a int, b int, c twoints generated always as (row(a,b)::twoints) not null); insert into foo values (null, null); I don't remember exactly what the rules are though so I may be wrong. -- Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/ "Having your biases confirmed independently is how scientific progress is made, and hence made our great society what it is today" (Mary Gardiner) ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-20 05:18 jian he <[email protected]> parent: Álvaro Herrera <[email protected]> 0 siblings, 2 replies; 60+ messages in thread From: jian he @ 2025-03-20 05:18 UTC (permalink / raw) To: Álvaro Herrera <[email protected]>; +Cc: Xuneng Zhou <[email protected]>; Navneet Kumar <[email protected]>; [email protected] On Thu, Mar 20, 2025 at 12:19 AM Álvaro Herrera <[email protected]> wrote: > > Other comments: > > * The block in ATRewriteTable that creates a resultRelInfo for > ExecRelCheckGenVirtualNotNull needs an explanation. > I tried my best. here are the comments above the line ``if (notnull_virtual_attrs != NIL)`` /* * Whether change an existing generation expression or adding a new * not-null virtual generated column, we need to evaluate whether the * generation expression is null. * In ExecConstraints, we use ExecRelCheckGenVirtualNotNull do the job. * Here, we can also utilize ExecRelCheckGenVirtualNotNull. * To achieve this, we need create a dummy ResultRelInfo. Ensure that * the resultRelationIndex of the dummy ResultRelInfo is set to 0. */ + /* + * XXX this deserves an explanation. Also, is rInfo a good variable + * name? + */ there are other places using this variable name: "rInfo", so i use these names.... ATRewriteTable: for (i = 0; i < newTupDesc->natts; i++) { Form_pg_attribute attr = TupleDescAttr(newTupDesc, i); if (attr->attnotnull && !attr->attisdropped) { if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) notnull_attrs = lappend_int(notnull_attrs, i); else notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, attr->attnum); } } this is kind of ugly? notnull_virtual_attrs is 1 based, notnull_attrs is 0 based. I want to change it all to 1 based. see v5-0002 > * I suspect the locations for the new functions were selected with > the help of a dartboard. ExecRelCheckGenVirtualNotNull() in > particular looks like it could use a better location. Maybe it's > better right after ExecConstraints, and ReportNotNullViolationError > (or whatever we name it) can go after it. I thought ExecRelCheckGenVirtualNotNull is very similar to ExecRelCheck, that's why I put it close to ExecRelCheck. putting it right after ExecConstraints is ok for me. > * I don't find the name all_virtual_nns particularly appropriate. Maybe > virtual_notnull_attrs? > in ATRewriteTable we already have "notnull_virtual_attrs" we can rename it to notnull_virtual_attrs > * There are some funny rules around nulls on rowtypes. I think allowing > this tuple is wrong (and I left an XXX comment near where the 'argisrow' > flag is set): > > create type twoints as (a int, b int); > create table foo (a int, b int, c twoints generated always as (row(a,b)::twoints) not null); > insert into foo values (null, null); > > I don't remember exactly what the rules are though so I may be wrong. > argisrow should set to false. i think you mean the special value ``'(,)'`` create table t(a twoints not null); insert into t select '(,)' returning a is null; --return true; create table t1(a twoints not null generated always as ('(,)'::twoints)); insert into t1 default values returning a is null; --should return true. i think you mean this thread: https://postgr.es/m/[email protected] should i put a test into generated_virtual.sql? + * We implement this by consing up a NullTest node for each virtual trivial question. I googled, and still found any explanation of the word "consing up". Attachments: [application/x-patch] v5-0001-not-null-for-virtual-generated-column.patch (33.1K, ../../CACJufxEoYA5ScUr2=CmA1xcpaS_1ixneDbEkVU77X1ctGxY2mA@mail.gmail.com/2-v5-0001-not-null-for-virtual-generated-column.patch) download | inline diff: From e7086ce90253907cc186e78c913670876af0bff3 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 20 Mar 2025 11:59:55 +0800 Subject: [PATCH v5 1/2] not null for virtual generated column MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit now we can add not null constraint on virtual generated column. not null constraint on virtual generated column make sure evaulation of the expanded generated expression does not yield null. the virtual generated columns does not store value, the storage is null. we do support ALTER COLUMN SET EXPRESSION over not null virtual generated column. reviewed by: Xuneng Zhou <[email protected]>, reviewed by: Navneet Kumar <[email protected]>, reviewed by: Álvaro Herrera <[email protected]> discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 10 - src/backend/commands/indexcmds.c | 10 +- src/backend/commands/tablecmds.c | 72 +++++- src/backend/executor/execMain.c | 244 ++++++++++++++---- src/backend/parser/parse_utilcmd.c | 14 - src/include/executor/executor.h | 4 + src/include/nodes/execnodes.h | 3 + .../regress/expected/generated_virtual.out | 89 +++++-- src/test/regress/sql/generated_virtual.sql | 50 +++- 9 files changed, 373 insertions(+), 123 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index bd3554c0bfd..b807ab66668 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -2615,11 +2615,6 @@ AddRelationNewConstraints(Relation rel, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(cdef->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), colnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * If the column already has a not-null constraint, we don't want @@ -2935,11 +2930,6 @@ AddRelationNotNullConstraints(Relation rel, List *constraints, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(constr->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), attnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * A column can only have one not-null constraint, so discard any diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 89cc83e8843..33c2106c17c 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -1118,10 +1118,12 @@ DefineIndex(Oid tableId, if (TupleDescAttr(RelationGetDescr(rel), attno - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - stmt->isconstraint ? - errmsg("unique constraints on virtual generated columns are not supported") : - errmsg("indexes on virtual generated columns are not supported"))); + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + stmt->primary ? + errmsg("primary keys on virtual generated columns are not supported") : + stmt->isconstraint ? + errmsg("unique constraints on virtual generated columns are not supported") : + errmsg("indexes on virtual generated columns are not supported")); } /* diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 129c97fdf28..0751c0d627c 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -6092,6 +6092,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) TupleDesc newTupDesc; bool needscan = false; List *notnull_attrs; + List *notnull_virtual_attrs; int i; ListCell *l; EState *estate; @@ -6176,22 +6177,30 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL); } - notnull_attrs = NIL; + notnull_attrs = notnull_virtual_attrs = NIL; if (newrel || tab->verify_new_notnull) { /* * If we are rebuilding the tuples OR if we added any new but not * verified not-null constraints, check all not-null constraints. This * is a bit of overkill but it minimizes risk of bugs. + * + * Collect attribute numbers on virtual generated columns separately! */ for (i = 0; i < newTupDesc->natts; i++) { Form_pg_attribute attr = TupleDescAttr(newTupDesc, i); if (attr->attnotnull && !attr->attisdropped) - notnull_attrs = lappend_int(notnull_attrs, i); + { + if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) + notnull_attrs = lappend_int(notnull_attrs, i); + else + notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, + attr->attnum); + } } - if (notnull_attrs) + if (notnull_attrs || notnull_virtual_attrs) needscan = true; } @@ -6205,6 +6214,32 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) List *dropped_attrs = NIL; ListCell *lc; Snapshot snapshot; + ResultRelInfo *rInfo = NULL; + + /* + * Whether change an existing generation expression or adding a new + * not-null virtual generated column, we need to evaluate whether the + * generation expression is null. + * In ExecConstraints, we use ExecRelCheckGenVirtualNotNull do the job. + * Here, we can also utilize ExecRelCheckGenVirtualNotNull. + * To achieve this, we need create a dummy ResultRelInfo. Ensure that + * the resultRelationIndex of the dummy ResultRelInfo is set to 0. + */ + if (notnull_virtual_attrs != NIL) + { + MemoryContext oldcontext; + + Assert(newTupDesc->constr->has_generated_virtual); + Assert(newTupDesc->constr->has_not_null); + oldcontext = MemoryContextSwitchTo(estate->es_query_cxt); + rInfo = makeNode(ResultRelInfo); + InitResultRelInfo(rInfo, + oldrel, + 0, /* dummy rangetable index */ + NULL, + estate->es_instrument); + MemoryContextSwitchTo(oldcontext); + } if (newrel) ereport(DEBUG1, @@ -6387,6 +6422,26 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) } } + if (notnull_virtual_attrs != NIL) + { + AttrNumber attnum; + + attnum = ExecRelCheckGenVirtualNotNull(rInfo, insertslot, + estate, + notnull_virtual_attrs); + if (attnum != InvalidAttrNumber) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attnum - 1); + + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of relation \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(oldrel)), + errtablecol(oldrel, attnum)); + } + } + foreach(l, tab->constraints) { NewConstraint *con = lfirst(l); @@ -7836,14 +7891,6 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName, errmsg("cannot alter system column \"%s\"", colName))); - /* TODO: see transformColumnDefinition() */ - if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", - colName, RelationGetRelationName(rel)))); - /* See if there's already a constraint */ tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum); if (HeapTupleIsValid(tuple)) @@ -8512,6 +8559,9 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName, errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", colName, RelationGetRelationName(rel)))); + if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL && attTup->attnotnull) + tab->verify_new_notnull = true; + /* * We need to prevent this because a change of expression could affect a * row filter and inject expressions that are not permitted in a row diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index e9bd98c7738..3ad2d35db4e 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -51,6 +51,7 @@ #include "foreign/fdwapi.h" #include "mb/pg_wchar.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/queryjumble.h" #include "parser/parse_relation.h" #include "pgstat.h" @@ -92,7 +93,9 @@ static bool ExecCheckPermissionsModified(Oid relOid, Oid userid, AclMode requiredPerms); static void ExecCheckXactReadOnly(PlannedStmt *plannedstmt); static void EvalPlanQualStart(EPQState *epqstate, Plan *planTree); - +static void ReportNotNullViolationError(ResultRelInfo *resultRelInfo, + TupleTableSlot *slot, + EState *estate, int attrChk); /* end of local decls */ @@ -1372,6 +1375,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo, resultRelInfo->ri_FdwState = NULL; resultRelInfo->ri_usesFdwDirectModify = false; resultRelInfo->ri_ConstraintExprs = NULL; + resultRelInfo->ri_GeneratedNotNullExprs = NULL; resultRelInfo->ri_GeneratedExprsI = NULL; resultRelInfo->ri_GeneratedExprsU = NULL; resultRelInfo->ri_projectReturning = NULL; @@ -2058,73 +2062,61 @@ ExecConstraints(ResultRelInfo *resultRelInfo, TupleDesc tupdesc = RelationGetDescr(rel); TupleConstr *constr = tupdesc->constr; Bitmapset *modifiedCols; + List *notnull_virtual_attrs = NIL; + bool virtual_notnull_check = false; Assert(constr); /* we should not be called otherwise */ + /* + * First, go over all the not-null constraints and verify and possibly + * throw errors for all of those that aren't on virtual generated columns. + * (The latter need executor support and a precise list of columns to + * handle, so we accumulate that here and initialize separately.) + */ if (constr->has_not_null) { - int natts = tupdesc->natts; - int attrChk; - - for (attrChk = 1; attrChk <= natts; attrChk++) + for (AttrNumber attnum = 1; attnum <= tupdesc->natts; attnum++) { - Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + Form_pg_attribute att = TupleDescAttr(tupdesc, attnum - 1); - if (att->attnotnull && slot_attisnull(slot, attrChk)) + if (att->attnotnull && att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, att->attnum); + + if (att->attnotnull && slot_attisnull(slot, attnum)) { - char *val_desc; - Relation orig_rel = rel; - TupleDesc orig_tupdesc = RelationGetDescr(rel); - - /* - * If the tuple has been routed, it's been converted to the - * partition's rowtype, which might differ from the root - * table's. We must convert it back to the root table's - * rowtype so that val_desc shown error message matches the - * input tuple. - */ - if (resultRelInfo->ri_RootResultRelInfo) + if (att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { - ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; - AttrMap *map; - - tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); - /* a reverse map */ - map = build_attrmap_by_name_if_req(orig_tupdesc, - tupdesc, - false); - - /* - * Partition-specific slot's tupdesc can't be changed, so - * allocate a new one. - */ - if (map != NULL) - slot = execute_attr_map_slot(map, slot, - MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); - modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), - ExecGetUpdatedCols(rootrel, estate)); - rel = rootrel->ri_RelationDesc; + if (!virtual_notnull_check) + virtual_notnull_check = true; + continue; } - else - modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), - ExecGetUpdatedCols(resultRelInfo, estate)); - val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), - slot, - tupdesc, - modifiedCols, - 64); - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", - NameStr(att->attname), - RelationGetRelationName(orig_rel)), - val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, - errtablecol(orig_rel, attrChk))); + ReportNotNullViolationError(resultRelInfo, slot, estate, attnum); } } } + /* Check not-null constraints on virtual generated column, if any */ + if (virtual_notnull_check) + { + AttrNumber attnum; + + Assert(constr->has_not_null); + Assert(constr->has_generated_virtual); + Assert(notnull_virtual_attrs != NIL); + + attnum = ExecRelCheckGenVirtualNotNull(resultRelInfo, slot, estate, + notnull_virtual_attrs); + if (attnum != InvalidAttrNumber) + { + Form_pg_attribute att = TupleDescAttr(tupdesc, attnum - 1); + + Assert(att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + ReportNotNullViolationError(resultRelInfo, slot, estate, att->attnum); + } + } + + /* Last, verify any CHECK constraints */ if (rel->rd_rel->relchecks > 0) { const char *failed; @@ -2134,7 +2126,12 @@ ExecConstraints(ResultRelInfo *resultRelInfo, char *val_desc; Relation orig_rel = rel; - /* See the comment above. */ + /* + * If the tuple has been routed, it's been converted to the + * partition's rowtype, which might differ from the root table's. + * We must convert it back to the root table's rowtype so that + * val_desc shown error message matches the input tuple. + */ if (resultRelInfo->ri_RootResultRelInfo) { ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; @@ -2176,6 +2173,145 @@ ExecConstraints(ResultRelInfo *resultRelInfo, } } +/* + * Verify not-null constraints on virtual generated columns of the given + * tuple slot. + * + * Return value of InvalidAttrNumber means all not-null constraints on virtual + * generated columns are satisfied. A return value > 0 means a not-null + * violation happened for that attribute. + * + * notnull_virtual_attrs is the list of the attnums of virtual generated column with + * not-null constraints. + */ +AttrNumber +ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, List *notnull_virtual_attrs) +{ + Relation rel = resultRelInfo->ri_RelationDesc; + ExprContext *econtext; + MemoryContext oldContext; + + /* + * We implement this by consing up a NullTest node for each virtual + * generated column, which we cache in resultRelInfo, and running those + * through ExecCheck. + */ + if (resultRelInfo->ri_GeneratedNotNullExprs == NULL) + { + int cnt = list_length(notnull_virtual_attrs); + + oldContext = MemoryContextSwitchTo(estate->es_query_cxt); + resultRelInfo->ri_GeneratedNotNullExprs = + (ExprState **) palloc0(cnt * sizeof(ExprState *)); + + foreach_int(attnum, notnull_virtual_attrs) + { + int i = foreach_current_index(attnum); + NullTest *nnulltest; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_generation_expression(rel, attnum); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + resultRelInfo->ri_GeneratedNotNullExprs[i] = + ExecPrepareExpr((Expr *) nnulltest, estate); + } + MemoryContextSwitchTo(oldContext); + } + + /* + * We will use the EState's per-tuple context for evaluating virtual + * generated column not null constraint expressions (creating it if it's + * not already there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + /* And evaluate the check constraints for virtual generated column */ + foreach_int(attnum, notnull_virtual_attrs) + { + int i = foreach_current_index(attnum); + ExprState *exprstate = resultRelInfo->ri_GeneratedNotNullExprs[i]; + + Assert(exprstate != NULL); + if (!ExecCheck(exprstate, econtext)) + return attnum; + } + + /* InvalidAttrNumber result means no error */ + return InvalidAttrNumber; +} + +/* + * Report a violation of a not-null constraint that was already detected. + */ +static void +ReportNotNullViolationError(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, int attrChk) +{ + Bitmapset *modifiedCols; + char *val_desc; + + Relation rel = resultRelInfo->ri_RelationDesc; + Relation orig_rel = rel; + + TupleDesc tupdesc = RelationGetDescr(rel); + TupleDesc orig_tupdesc = RelationGetDescr(rel); + Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + + Assert(attrChk > 0); + + /* + * If the tuple has been routed, it's been converted to the partition's + * rowtype, which might differ from the root table's. We must convert it + * back to the root table's rowtype so that val_desc shown error message + * matches the input tuple. + */ + if (resultRelInfo->ri_RootResultRelInfo) + { + ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; + AttrMap *map; + + tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); + /* a reverse map */ + map = build_attrmap_by_name_if_req(orig_tupdesc, + tupdesc, + false); + + /* + * Partition-specific slot's tupdesc can't be changed, so allocate a + * new one. + */ + if (map != NULL) + slot = execute_attr_map_slot(map, slot, + MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); + modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), + ExecGetUpdatedCols(rootrel, estate)); + rel = rootrel->ri_RelationDesc; + } + else + modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), + ExecGetUpdatedCols(resultRelInfo, estate)); + + val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), + slot, + tupdesc, + modifiedCols, + 64); + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", + NameStr(att->attname), + RelationGetRelationName(orig_rel)), + val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, + errtablecol(orig_rel, attrChk)); +} + /* * ExecWithCheckOptions -- check that tuple satisfies any WITH CHECK OPTIONs * of the specified kind. diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index 896a7f2c59b..9c1541e1fea 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -988,20 +988,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); - - /* - * TODO: Straightforward not-null constraints won't work on virtual - * generated columns, because there is no support for expanding the - * column when the constraint is checked. Maybe we could convert the - * not-null constraint into a full check constraint, so that the - * generation expression can be expanded at check time. - */ - if (column->is_not_null && column->generated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - parser_errposition(cxt->pstate, - constraint->location))); } /* diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index 0db5d18ba22..7a2525e8ce1 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -220,6 +220,10 @@ extern ResultRelInfo *ExecGetTriggerResultRel(EState *estate, Oid relid, extern List *ExecGetAncestorResultRels(EState *estate, ResultRelInfo *resultRelInfo); extern void ExecConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate); +extern AttrNumber ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, + TupleTableSlot *slot, + EState *estate, + List *notnull_virtual_attrs); extern bool ExecPartitionCheck(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate, bool emitError); extern void ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index d4d4e655180..6159b8a3c07 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -549,6 +549,9 @@ typedef struct ResultRelInfo /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_GeneratedNotNullExprs; + /* * Arrays of stored generated columns ExprStates for INSERT/UPDATE/MERGE. */ diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index dc09c85938e..98f2e486f88 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -664,28 +664,68 @@ INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails ERROR: new row for relation "gtest20c" violates check constraint "whole_row_check" DETAIL: Failing row contains (null, virtual). --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); -ERROR: not-null constraints are not supported on virtual generated columns -LINE 1: ... b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); - ^ ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21a" violates not-null constraint +DETAIL: Failing row contains (0, virtual). -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error -ERROR: not-null constraints are not supported on virtual generated columns +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +ERROR: column "b" of relation "gtest21ax" contains null values +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error -ERROR: not-null constraints are not supported on virtual generated columns +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; -ERROR: not-null constraints are not supported on virtual generated columns -DETAIL: Column "b" of relation "gtest21b" is a virtual generated column. ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21b (a) VALUES (NULL); -- error +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (null, virtual). ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (1, 2, virtual). +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (2, 10, virtual). +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +ERROR: column "f3" of relation "gtestnn_child" contains null values +INSERT INTO gtestnn_parent VALUES (10, 11, default); --error +select * from gtestnn_parent; + f1 | f2 | f3 +----+----+---- + 2 | 2 | 4 + 3 | 5 | 8 + 14 | 12 | 26 + 10 | 11 | 21 +(4 rows) + +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_childdef" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_child" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); ERROR: unique constraints on virtual generated columns are not supported @@ -693,7 +733,7 @@ ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22a VALUES (3); --INSERT INTO gtest22a VALUES (4); CREATE TABLE gtest22b (a int, b int GENERATED ALWAYS AS (a / 2) VIRTUAL, PRIMARY KEY (a, b)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary keys on virtual generated columns are not supported --INSERT INTO gtest22b VALUES (2); --INSERT INTO gtest22b VALUES (2); -- indexes @@ -738,7 +778,7 @@ ERROR: foreign key constraints on virtual generated columns are not supported --DROP TABLE gtest23b; --DROP TABLE gtest23a; CREATE TABLE gtest23p (x int, y int GENERATED ALWAYS AS (x * 2) VIRTUAL, PRIMARY KEY (y)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary keys on virtual generated columns are not supported --INSERT INTO gtest23p VALUES (1), (2), (3); CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); ERROR: relation "gtest23p" does not exist @@ -1029,7 +1069,7 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ERROR: cannot alter type of a column used by a generated column DETAIL: Column "a" is used by generated column "x". @@ -1047,7 +1087,8 @@ SELECT * FROM gtest27; ---+----+---- 3 | 7 | 20 4 | 11 | 30 -(2 rows) + | | +(3 rows) ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ERROR: cannot specify USING when altering type of generated column @@ -1056,6 +1097,14 @@ LINE 1: ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0... DETAIL: Column "x" is a generated column. ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error ERROR: column "x" of relation "gtest27" is a generated column +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +ERROR: column "x" of relation "gtest27" contains null values +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index dab8c92ef99..485e2a317fe 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -335,23 +335,46 @@ ALTER TABLE gtest20c ADD CONSTRAINT whole_row_check CHECK (gtest20c IS NOT NULL) INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +DROP TABLE gtest21ax; + CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (NULL); -- error ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now + +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent(f1 int, f2 bigint, f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +INSERT INTO gtestnn_parent VALUES (10, 11, default); --error +select * from gtestnn_parent; +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); @@ -524,13 +547,20 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ALTER TABLE gtest27 ALTER COLUMN x TYPE numeric; \d gtest27 SELECT * FROM gtest27; ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, -- 2.34.1 [application/x-patch] v5-0002-minor-change-ATRewriteTable.patch (1.8K, ../../CACJufxEoYA5ScUr2=CmA1xcpaS_1ixneDbEkVU77X1ctGxY2mA@mail.gmail.com/3-v5-0002-minor-change-ATRewriteTable.patch) download | inline diff: From 8b99e21fda58a0189547139b4aa2ba9f87eabbb7 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 20 Mar 2025 12:06:41 +0800 Subject: [PATCH v5 2/2] minor change ATRewriteTable make notnull_attrs and notnull_virtual_attrs both are 1 based. make sure TupleDescAttr need minus 1. --- src/backend/commands/tablecmds.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 0751c0d627c..04806c068df 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -6194,7 +6194,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) if (attr->attnotnull && !attr->attisdropped) { if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) - notnull_attrs = lappend_int(notnull_attrs, i); + notnull_attrs = lappend_int(notnull_attrs, attr->attnum); else notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, attr->attnum); @@ -6405,20 +6405,18 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) /* Now check any constraints on the possibly-changed tuple */ econtext->ecxt_scantuple = insertslot; - foreach(l, notnull_attrs) + foreach_int(attn, notnull_attrs) { - int attn = lfirst_int(l); - - if (slot_attisnull(insertslot, attn + 1)) + if (slot_attisnull(insertslot, attn)) { - Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn); + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn - 1); ereport(ERROR, (errcode(ERRCODE_NOT_NULL_VIOLATION), errmsg("column \"%s\" of relation \"%s\" contains null values", NameStr(attr->attname), RelationGetRelationName(oldrel)), - errtablecol(oldrel, attn + 1))); + errtablecol(oldrel, attn))); } } -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-21 04:33 Xuneng Zhou <[email protected]> parent: jian he <[email protected]> 1 sibling, 0 replies; 60+ messages in thread From: Xuneng Zhou @ 2025-03-21 04:33 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: Álvaro Herrera <[email protected]>; Navneet Kumar <[email protected]>; pgsql-hackers Hi, response from ChatGPT, seems correct: "Consing up" is an informal term derived from Lisp terminology. In this context, it means dynamically creating (allocating and constructing) a new NullTest node. Instead of reusing an existing node, the code allocates a fresh node—using PostgreSQL’s memory allocation (palloc) functions—and fills in its fields (like the generation expression, null test type, etc.). This new node is then prepared (compiled) for execution with ExecPrepareExpr and used to evaluate whether the generated expression returns a non-NULL value, thus enforcing the NOT NULL constraint on virtual generated columns. > > + * We implement this by consing up a NullTest node for each virtual > trivial question. > I googled, and still found any explanation of the word "consing up". > ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-21 10:18 Álvaro Herrera <[email protected]> parent: jian he <[email protected]> 1 sibling, 1 reply; 60+ messages in thread From: Álvaro Herrera @ 2025-03-21 10:18 UTC (permalink / raw) To: jian he <[email protected]>; +Cc: Xuneng Zhou <[email protected]>; Navneet Kumar <[email protected]>; [email protected] On 2025-Mar-20, jian he wrote: > ATRewriteTable: > for (i = 0; i < newTupDesc->natts; i++) > { > Form_pg_attribute attr = TupleDescAttr(newTupDesc, i); > if (attr->attnotnull && !attr->attisdropped) > { > if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) > notnull_attrs = lappend_int(notnull_attrs, i); > else > notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, > attr->attnum); > } > } > this is kind of ugly? notnull_virtual_attrs is 1 based, notnull_attrs > is 0 based. > I want to change it all to 1 based. see v5-0002 Yeah, this inconsistency bothered me too. I have pushed your 0002 now, which means your 0001 needs a small rebase. I'm going to leave 0001 for Peter to commit, as it's mostly his turf. > + * We implement this by consing up a NullTest node for each virtual > trivial question. > I googled, and still found any explanation of the word "consing up". https://www.pc-freak.net/files/the-hacker-disctionary.html You could change "cons up" to "manufacture" in that comment and get about the same meaning. Maybe have a look at git grep -C3 -E 'cons(|ing|ed) up' I think the ChatGPT answer quoted by Zhou is roughly on point. -- Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/ "El que vive para el futuro es un iluso, y el que vive para el pasado, un imbécil" (Luis Adler, "Los tripulantes de la noche") ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-24 03:26 jian he <[email protected]> parent: Álvaro Herrera <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: jian he @ 2025-03-24 03:26 UTC (permalink / raw) To: Álvaro Herrera <[email protected]>; +Cc: Xuneng Zhou <[email protected]>; Navneet Kumar <[email protected]>; [email protected] hi. rebase, and some minor code comments change. Attachments: [text/x-patch] v6-0001-not-null-for-virtual-generated-column.patch (33.4K, ../../CACJufxEUg7KFv2qXW-wKH1NcSx5GkROXbjML254KtjxvOiwB+g@mail.gmail.com/2-v6-0001-not-null-for-virtual-generated-column.patch) download | inline diff: From 0af096b3959cc6f146bbe8a54a018c0e69beff2e Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Mon, 24 Mar 2025 11:22:54 +0800 Subject: [PATCH v6 1/1] not null for virtual generated column MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit now we can add not null constraint on virtual generated column. virtual generated colunm the storage is still null. but not null constraint on virtual generated column make sure evaulation of the expanded generated expression does not yield null. we do support ALTER COLUMN SET EXPRESSION over not null virtual generated column. reviewed by: Xuneng Zhou <[email protected]>, reviewed by: Navneet Kumar <[email protected]>, reviewed by: Álvaro Herrera <[email protected]> discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 10 - src/backend/commands/indexcmds.c | 10 +- src/backend/commands/tablecmds.c | 74 +++++- src/backend/executor/execMain.c | 245 ++++++++++++++---- src/backend/parser/parse_utilcmd.c | 14 - src/include/executor/executor.h | 4 + src/include/nodes/execnodes.h | 3 + .../regress/expected/generated_virtual.out | 93 +++++-- src/test/regress/sql/generated_virtual.sql | 54 +++- 9 files changed, 384 insertions(+), 123 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index bd3554c0bfd..b807ab66668 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -2615,11 +2615,6 @@ AddRelationNewConstraints(Relation rel, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(cdef->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), colnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * If the column already has a not-null constraint, we don't want @@ -2935,11 +2930,6 @@ AddRelationNotNullConstraints(Relation rel, List *constraints, errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot add not-null constraint on system column \"%s\"", strVal(linitial(constr->keys)))); - /* TODO: see transformColumnDefinition() */ - if (get_attgenerated(RelationGetRelid(rel), attnum) == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns")); /* * A column can only have one not-null constraint, so discard any diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 89cc83e8843..33c2106c17c 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -1118,10 +1118,12 @@ DefineIndex(Oid tableId, if (TupleDescAttr(RelationGetDescr(rel), attno - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - stmt->isconstraint ? - errmsg("unique constraints on virtual generated columns are not supported") : - errmsg("indexes on virtual generated columns are not supported"))); + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + stmt->primary ? + errmsg("primary keys on virtual generated columns are not supported") : + stmt->isconstraint ? + errmsg("unique constraints on virtual generated columns are not supported") : + errmsg("indexes on virtual generated columns are not supported")); } /* diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 1202544ebd0..503be7e0f7e 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -6092,6 +6092,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) TupleDesc newTupDesc; bool needscan = false; List *notnull_attrs; + List *notnull_virtual_attrs; int i; ListCell *l; EState *estate; @@ -6176,22 +6177,32 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL); } - notnull_attrs = NIL; + notnull_attrs = notnull_virtual_attrs = NIL; if (newrel || tab->verify_new_notnull) { /* * If we are rebuilding the tuples OR if we added any new but not * verified not-null constraints, check all not-null constraints. This * is a bit of overkill but it minimizes risk of bugs. + * + * notnull_attrs does *not* collect attribute numbers for not-null + * constraints over virtual generated columns; instead, they are + * collected in notnull_virtual_attrs. */ for (i = 0; i < newTupDesc->natts; i++) { Form_pg_attribute attr = TupleDescAttr(newTupDesc, i); if (attr->attnotnull && !attr->attisdropped) - notnull_attrs = lappend_int(notnull_attrs, attr->attnum); + { + if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) + notnull_attrs = lappend_int(notnull_attrs, attr->attnum); + else + notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, + attr->attnum); + } } - if (notnull_attrs) + if (notnull_attrs || notnull_virtual_attrs) needscan = true; } @@ -6205,6 +6216,32 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) List *dropped_attrs = NIL; ListCell *lc; Snapshot snapshot; + ResultRelInfo *rInfo = NULL; + + /* + * Whether change an existing generation expression or adding a new + * not-null virtual generated column, we need to evaluate whether the + * generation expression is null. + * In ExecConstraints, we use ExecRelCheckGenVirtualNotNull do the job. + * Here, we can also utilize ExecRelCheckGenVirtualNotNull too. + * To achieve this, we need create a dummy ResultRelInfo. Ensure that + * the resultRelationIndex of the dummy ResultRelInfo is set to 0. + */ + if (notnull_virtual_attrs != NIL) + { + MemoryContext oldcontext; + + Assert(newTupDesc->constr->has_generated_virtual); + Assert(newTupDesc->constr->has_not_null); + oldcontext = MemoryContextSwitchTo(estate->es_query_cxt); + rInfo = makeNode(ResultRelInfo); + InitResultRelInfo(rInfo, + oldrel, + 0, /* dummy rangetable index */ + NULL, + estate->es_instrument); + MemoryContextSwitchTo(oldcontext); + } if (newrel) ereport(DEBUG1, @@ -6385,6 +6422,26 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) } } + if (notnull_virtual_attrs != NIL) + { + AttrNumber attnum; + + attnum = ExecRelCheckGenVirtualNotNull(rInfo, insertslot, + estate, + notnull_virtual_attrs); + if (attnum != InvalidAttrNumber) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, attnum - 1); + + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of relation \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(oldrel)), + errtablecol(oldrel, attnum)); + } + } + foreach(l, tab->constraints) { NewConstraint *con = lfirst(l); @@ -7834,14 +7891,6 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName, errmsg("cannot alter system column \"%s\"", colName))); - /* TODO: see transformColumnDefinition() */ - if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", - colName, RelationGetRelationName(rel)))); - /* See if there's already a constraint */ tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum); if (HeapTupleIsValid(tuple)) @@ -8510,6 +8559,9 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName, errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.", colName, RelationGetRelationName(rel)))); + if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL && attTup->attnotnull) + tab->verify_new_notnull = true; + /* * We need to prevent this because a change of expression could affect a * row filter and inject expressions that are not permitted in a row diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index e9bd98c7738..f90fc001185 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -51,6 +51,7 @@ #include "foreign/fdwapi.h" #include "mb/pg_wchar.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/queryjumble.h" #include "parser/parse_relation.h" #include "pgstat.h" @@ -92,7 +93,9 @@ static bool ExecCheckPermissionsModified(Oid relOid, Oid userid, AclMode requiredPerms); static void ExecCheckXactReadOnly(PlannedStmt *plannedstmt); static void EvalPlanQualStart(EPQState *epqstate, Plan *planTree); - +static void ReportNotNullViolationError(ResultRelInfo *resultRelInfo, + TupleTableSlot *slot, + EState *estate, int attrChk); /* end of local decls */ @@ -1372,6 +1375,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo, resultRelInfo->ri_FdwState = NULL; resultRelInfo->ri_usesFdwDirectModify = false; resultRelInfo->ri_ConstraintExprs = NULL; + resultRelInfo->ri_GeneratedNotNullExprs = NULL; resultRelInfo->ri_GeneratedExprsI = NULL; resultRelInfo->ri_GeneratedExprsU = NULL; resultRelInfo->ri_projectReturning = NULL; @@ -2058,73 +2062,61 @@ ExecConstraints(ResultRelInfo *resultRelInfo, TupleDesc tupdesc = RelationGetDescr(rel); TupleConstr *constr = tupdesc->constr; Bitmapset *modifiedCols; + List *notnull_virtual_attrs = NIL; + bool virtual_notnull_check = false; Assert(constr); /* we should not be called otherwise */ + /* + * First, go over all the not-null constraints and verify and possibly + * throw errors for all of those that aren't on virtual generated columns. + * (The latter need executor support and a precise list of columns to + * handle, so we accumulate that here and initialize separately.) + */ if (constr->has_not_null) { - int natts = tupdesc->natts; - int attrChk; - - for (attrChk = 1; attrChk <= natts; attrChk++) + for (AttrNumber attnum = 1; attnum <= tupdesc->natts; attnum++) { - Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + Form_pg_attribute att = TupleDescAttr(tupdesc, attnum - 1); - if (att->attnotnull && slot_attisnull(slot, attrChk)) + if (att->attnotnull && att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + notnull_virtual_attrs = lappend_int(notnull_virtual_attrs, att->attnum); + + if (att->attnotnull && slot_attisnull(slot, attnum)) { - char *val_desc; - Relation orig_rel = rel; - TupleDesc orig_tupdesc = RelationGetDescr(rel); - - /* - * If the tuple has been routed, it's been converted to the - * partition's rowtype, which might differ from the root - * table's. We must convert it back to the root table's - * rowtype so that val_desc shown error message matches the - * input tuple. - */ - if (resultRelInfo->ri_RootResultRelInfo) + if (att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { - ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; - AttrMap *map; - - tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); - /* a reverse map */ - map = build_attrmap_by_name_if_req(orig_tupdesc, - tupdesc, - false); - - /* - * Partition-specific slot's tupdesc can't be changed, so - * allocate a new one. - */ - if (map != NULL) - slot = execute_attr_map_slot(map, slot, - MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); - modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), - ExecGetUpdatedCols(rootrel, estate)); - rel = rootrel->ri_RelationDesc; + if (!virtual_notnull_check) + virtual_notnull_check = true; + continue; } - else - modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), - ExecGetUpdatedCols(resultRelInfo, estate)); - val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), - slot, - tupdesc, - modifiedCols, - 64); - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", - NameStr(att->attname), - RelationGetRelationName(orig_rel)), - val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, - errtablecol(orig_rel, attrChk))); + ReportNotNullViolationError(resultRelInfo, slot, estate, attnum); } } } + /* Check not-null constraints on virtual generated column, if any */ + if (virtual_notnull_check) + { + AttrNumber attnum; + + Assert(constr->has_not_null); + Assert(constr->has_generated_virtual); + Assert(notnull_virtual_attrs != NIL); + + attnum = ExecRelCheckGenVirtualNotNull(resultRelInfo, slot, estate, + notnull_virtual_attrs); + if (attnum != InvalidAttrNumber) + { + Form_pg_attribute att = TupleDescAttr(tupdesc, attnum - 1); + + Assert(att->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + ReportNotNullViolationError(resultRelInfo, slot, estate, att->attnum); + } + } + + /* Last, verify any CHECK constraints */ if (rel->rd_rel->relchecks > 0) { const char *failed; @@ -2134,7 +2126,12 @@ ExecConstraints(ResultRelInfo *resultRelInfo, char *val_desc; Relation orig_rel = rel; - /* See the comment above. */ + /* + * If the tuple has been routed, it's been converted to the + * partition's rowtype, which might differ from the root table's. + * We must convert it back to the root table's rowtype so that + * val_desc shown error message matches the input tuple. + */ if (resultRelInfo->ri_RootResultRelInfo) { ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; @@ -2176,6 +2173,146 @@ ExecConstraints(ResultRelInfo *resultRelInfo, } } +/* + * Verify not-null constraints on virtual generated columns of the given + * tuple slot. + * + * Return value of InvalidAttrNumber means all not-null constraints on virtual + * generated columns are satisfied. A return value > 0 means a not-null + * violation happened for that attribute. + * + * notnull_virtual_attrs is the list of the attnums of virtual generated column with + * not-null constraints. + */ +AttrNumber +ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, List *notnull_virtual_attrs) +{ + Relation rel = resultRelInfo->ri_RelationDesc; + ExprContext *econtext; + MemoryContext oldContext; + + /* + * We implement this by consing up a NullTest node for each virtual + * generated column, which we cache in resultRelInfo, and running those + * through ExecCheck. + */ + if (resultRelInfo->ri_GeneratedNotNullExprs == NULL) + { + int cnt = list_length(notnull_virtual_attrs); + + oldContext = MemoryContextSwitchTo(estate->es_query_cxt); + resultRelInfo->ri_GeneratedNotNullExprs = + (ExprState **) palloc0(cnt * sizeof(ExprState *)); + + foreach_int(attnum, notnull_virtual_attrs) + { + int i = foreach_current_index(attnum); + NullTest *nnulltest; + + /* "generated_expression IS NOT NULL" check. */ + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_generation_expression(rel, attnum); + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + resultRelInfo->ri_GeneratedNotNullExprs[i] = + ExecPrepareExpr((Expr *) nnulltest, estate); + } + MemoryContextSwitchTo(oldContext); + } + + /* + * We will use the EState's per-tuple context for evaluating virtual + * generated column not null constraint expressions (creating it if it's + * not already there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + /* And evaluate the check constraints for virtual generated column */ + foreach_int(attnum, notnull_virtual_attrs) + { + int i = foreach_current_index(attnum); + ExprState *exprstate = resultRelInfo->ri_GeneratedNotNullExprs[i]; + + Assert(exprstate != NULL); + if (!ExecCheck(exprstate, econtext)) + return attnum; + } + + /* InvalidAttrNumber result means no error */ + return InvalidAttrNumber; +} + +/* + * Report a violation of a not-null constraint that was already detected. + */ +static void +ReportNotNullViolationError(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, + EState *estate, int attrChk) +{ + Bitmapset *modifiedCols; + char *val_desc; + + Relation rel = resultRelInfo->ri_RelationDesc; + Relation orig_rel = rel; + + TupleDesc tupdesc = RelationGetDescr(rel); + TupleDesc orig_tupdesc = RelationGetDescr(rel); + Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1); + + Assert(attrChk > 0); + + /* + * If the tuple has been routed, it's been converted to the partition's + * rowtype, which might differ from the root table's. We must convert it + * back to the root table's rowtype so that val_desc shown error message + * matches the input tuple. + */ + if (resultRelInfo->ri_RootResultRelInfo) + { + ResultRelInfo *rootrel = resultRelInfo->ri_RootResultRelInfo; + AttrMap *map; + + tupdesc = RelationGetDescr(rootrel->ri_RelationDesc); + /* a reverse map */ + map = build_attrmap_by_name_if_req(orig_tupdesc, + tupdesc, + false); + + /* + * Partition-specific slot's tupdesc can't be changed, so allocate a + * new one. + */ + if (map != NULL) + slot = execute_attr_map_slot(map, slot, + MakeTupleTableSlot(tupdesc, &TTSOpsVirtual)); + modifiedCols = bms_union(ExecGetInsertedCols(rootrel, estate), + ExecGetUpdatedCols(rootrel, estate)); + rel = rootrel->ri_RelationDesc; + } + else + modifiedCols = bms_union(ExecGetInsertedCols(resultRelInfo, estate), + ExecGetUpdatedCols(resultRelInfo, estate)); + + val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel), + slot, + tupdesc, + modifiedCols, + 64); + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint", + NameStr(att->attname), + RelationGetRelationName(orig_rel)), + val_desc ? errdetail("Failing row contains %s.", val_desc) : 0, + errtablecol(orig_rel, attrChk)); +} + /* * ExecWithCheckOptions -- check that tuple satisfies any WITH CHECK OPTIONs * of the specified kind. diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index 896a7f2c59b..9c1541e1fea 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -988,20 +988,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); - - /* - * TODO: Straightforward not-null constraints won't work on virtual - * generated columns, because there is no support for expanding the - * column when the constraint is checked. Maybe we could convert the - * not-null constraint into a full check constraint, so that the - * generation expression can be expanded at check time. - */ - if (column->is_not_null && column->generated == ATTRIBUTE_GENERATED_VIRTUAL) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("not-null constraints are not supported on virtual generated columns"), - parser_errposition(cxt->pstate, - constraint->location))); } /* diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index 0db5d18ba22..7a2525e8ce1 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -220,6 +220,10 @@ extern ResultRelInfo *ExecGetTriggerResultRel(EState *estate, Oid relid, extern List *ExecGetAncestorResultRels(EState *estate, ResultRelInfo *resultRelInfo); extern void ExecConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate); +extern AttrNumber ExecRelCheckGenVirtualNotNull(ResultRelInfo *resultRelInfo, + TupleTableSlot *slot, + EState *estate, + List *notnull_virtual_attrs); extern bool ExecPartitionCheck(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate, bool emitError); extern void ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo, diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index d4d4e655180..6159b8a3c07 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -549,6 +549,9 @@ typedef struct ResultRelInfo /* array of constraint-checking expr states */ ExprState **ri_ConstraintExprs; + /* array of virtual generated not null constraint-checking expr states */ + ExprState **ri_GeneratedNotNullExprs; + /* * Arrays of stored generated columns ExprStates for INSERT/UPDATE/MERGE. */ diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index dc09c85938e..98108191be1 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -664,28 +664,72 @@ INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails ERROR: new row for relation "gtest20c" violates check constraint "whole_row_check" DETAIL: Failing row contains (null, virtual). --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); -ERROR: not-null constraints are not supported on virtual generated columns -LINE 1: ... b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); - ^ ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21a" violates not-null constraint +DETAIL: Failing row contains (0, virtual). -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error -ERROR: not-null constraints are not supported on virtual generated columns +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +ERROR: column "b" of relation "gtest21ax" contains null values +DROP TABLE gtest21ax; CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error -ERROR: not-null constraints are not supported on virtual generated columns +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21ax" violates not-null constraint +DETAIL: Failing row contains (0, virtual). DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; -ERROR: not-null constraints are not supported on virtual generated columns -DETAIL: Column "b" of relation "gtest21b" is a virtual generated column. ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (0, virtual). +INSERT INTO gtest21b (a) VALUES (NULL); -- error +ERROR: null value in column "b" of relation "gtest21b" violates not-null constraint +DETAIL: Failing row contains (null, virtual). ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent( + f1 int, + f2 bigint, + f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) + PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (1, 2, virtual). +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ERROR: null value in column "f3" of relation "gtestnn_child" violates not-null constraint +DETAIL: Failing row contains (2, 10, virtual). +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +ERROR: column "f3" of relation "gtestnn_child" contains null values +INSERT INTO gtestnn_parent VALUES (10, 11, default); --ok +SELECT * FROM gtestnn_parent ORDER BY f1, f2, f3; + f1 | f2 | f3 +----+----+---- + 2 | 2 | 4 + 3 | 5 | 8 + 10 | 11 | 21 + 14 | 12 | 26 +(4 rows) + +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_childdef" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ERROR: column "c" of relation "gtestnn_child" contains null values +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); ERROR: unique constraints on virtual generated columns are not supported @@ -693,7 +737,7 @@ ERROR: unique constraints on virtual generated columns are not supported --INSERT INTO gtest22a VALUES (3); --INSERT INTO gtest22a VALUES (4); CREATE TABLE gtest22b (a int, b int GENERATED ALWAYS AS (a / 2) VIRTUAL, PRIMARY KEY (a, b)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary keys on virtual generated columns are not supported --INSERT INTO gtest22b VALUES (2); --INSERT INTO gtest22b VALUES (2); -- indexes @@ -738,7 +782,7 @@ ERROR: foreign key constraints on virtual generated columns are not supported --DROP TABLE gtest23b; --DROP TABLE gtest23a; CREATE TABLE gtest23p (x int, y int GENERATED ALWAYS AS (x * 2) VIRTUAL, PRIMARY KEY (y)); -ERROR: not-null constraints are not supported on virtual generated columns +ERROR: primary keys on virtual generated columns are not supported --INSERT INTO gtest23p VALUES (1), (2), (3); CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); ERROR: relation "gtest23p" does not exist @@ -1029,7 +1073,7 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ERROR: cannot alter type of a column used by a generated column DETAIL: Column "a" is used by generated column "x". @@ -1047,7 +1091,8 @@ SELECT * FROM gtest27; ---+----+---- 3 | 7 | 20 4 | 11 | 30 -(2 rows) + | | +(3 rows) ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ERROR: cannot specify USING when altering type of generated column @@ -1056,6 +1101,14 @@ LINE 1: ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0... DETAIL: Column "x" is a generated column. ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error ERROR: column "x" of relation "gtest27" is a generated column +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +ERROR: column "x" of relation "gtest27" contains null values +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index dab8c92ef99..6624d0b22eb 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -335,23 +335,50 @@ ALTER TABLE gtest20c ADD CONSTRAINT whole_row_check CHECK (gtest20c IS NOT NULL) INSERT INTO gtest20c VALUES (1); -- ok INSERT INTO gtest20c VALUES (NULL); -- fails --- not-null constraints (currently not supported) CREATE TABLE gtest21a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL NOT NULL); ---INSERT INTO gtest21a (a) VALUES (1); -- ok ---INSERT INTO gtest21a (a) VALUES (0); -- violates constraint +INSERT INTO gtest21a (a) VALUES (1); -- ok +INSERT INTO gtest21a (a) VALUES (0); -- violates constraint -- also check with table constraint syntax -CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); -- error +CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL, CONSTRAINT cc NOT NULL b); +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint +INSERT INTO gtest21ax (a) VALUES (1); --ok +-- SET EXPRESSION support not null constraint +ALTER TABLE gtest21ax ALTER COLUMN b SET EXPRESSION AS (nullif(a, 1)); --error +DROP TABLE gtest21ax; + CREATE TABLE gtest21ax (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); -ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; -- error +ALTER TABLE gtest21ax ADD CONSTRAINT cc NOT NULL b; +INSERT INTO gtest21ax (a) VALUES (0); -- violates constraint DROP TABLE gtest21ax; -CREATE TABLE gtest21b (a int PRIMARY KEY, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); +CREATE TABLE gtest21b (a int, b int GENERATED ALWAYS AS (nullif(a, 0)) VIRTUAL); ALTER TABLE gtest21b ALTER COLUMN b SET NOT NULL; ---INSERT INTO gtest21b (a) VALUES (1); -- ok ---INSERT INTO gtest21b (a) VALUES (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (1); -- ok +INSERT INTO gtest21b (a) VALUES (2), (0); -- violates constraint +INSERT INTO gtest21b (a) VALUES (NULL); -- error ALTER TABLE gtest21b ALTER COLUMN b DROP NOT NULL; ---INSERT INTO gtest21b (a) VALUES (0); -- ok now +INSERT INTO gtest21b (a) VALUES (0); -- ok now + +--not null constraint with partitioned table case. +CREATE TABLE gtestnn_parent( + f1 int, + f2 bigint, + f3 bigint GENERATED ALWAYS AS (nullif(f1, 1) + nullif(f2, 10)) VIRTUAL not null) + PARTITION BY RANGE (f1); +CREATE TABLE gtestnn_child PARTITION OF gtestnn_parent FOR VALUES FROM (1) TO (5); +CREATE TABLE gtestnn_childdef PARTITION OF gtestnn_parent default; +--check the error message. +INSERT INTO gtestnn_parent VALUES (2, 2, default), (3, 5, default), (14, 12, default); +INSERT INTO gtestnn_parent VALUES (1, 2, default); --error +INSERT INTO gtestnn_parent VALUES (2, 10, default); --error +ALTER TABLE gtestnn_parent ALTER COLUMN f3 SET EXPRESSION AS (nullif(f1, 2) + nullif(f2, 11)); --error +INSERT INTO gtestnn_parent VALUES (10, 11, default); --ok +SELECT * FROM gtestnn_parent ORDER BY f1, f2, f3; +--test ALTER TABLE ADD COLUMN. +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 14) + nullif(f2, 10)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 13) + nullif(f2, 5)) VIRTUAL; --error +ALTER TABLE gtestnn_parent ADD COLUMN c int NOT NULL GENERATED ALWAYS AS (nullif(f1, 4) + nullif(f2, 6)) VIRTUAL; --ok -- index constraints CREATE TABLE gtest22a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a / 2) VIRTUAL UNIQUE); @@ -524,13 +551,20 @@ CREATE TABLE gtest27 ( b int, x int GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL ); -INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11); +INSERT INTO gtest27 (a, b) VALUES (3, 7), (4, 11), (NULL, NULL); ALTER TABLE gtest27 ALTER COLUMN a TYPE text; -- error ALTER TABLE gtest27 ALTER COLUMN x TYPE numeric; \d gtest27 SELECT * FROM gtest27; ALTER TABLE gtest27 ALTER COLUMN x TYPE boolean USING x <> 0; -- error ALTER TABLE gtest27 ALTER COLUMN x DROP DEFAULT; -- error +--not null error violation +ALTER TABLE gtest27 + DROP COLUMN x, + ALTER COLUMN a TYPE bigint, + ALTER COLUMN b TYPE bigint, + ADD COLUMN x bigint GENERATED ALWAYS AS ((a + b) * 2) VIRTUAL NOT NULL; +DELETE FROM gtest27 WHERE a IS NULL AND b IS NULL; -- It's possible to alter the column types this way: ALTER TABLE gtest27 DROP COLUMN x, -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-28 14:06 Peter Eisentraut <[email protected]> parent: jian he <[email protected]> 0 siblings, 1 reply; 60+ messages in thread From: Peter Eisentraut @ 2025-03-28 14:06 UTC (permalink / raw) To: jian he <[email protected]>; Álvaro Herrera <[email protected]>; +Cc: Xuneng Zhou <[email protected]>; Navneet Kumar <[email protected]>; [email protected] On 24.03.25 04:26, jian he wrote: > rebase, and some minor code comments change. I have committed this. I did a bit more editing on the naming of various things. In terms of functionality, in ExecConstraints() notnull_virtual_attrs and virtual_notnull_check were redundant, so I simplified that. I also cut back a little bit on the assertions. They were all ok, but I felt in some places they bloated the code quite a bit for no real gain. ^ permalink raw reply [nested|flat] 60+ messages in thread
* Re: support virtual generated column not null constraint @ 2025-03-31 07:26 jian he <[email protected]> parent: Peter Eisentraut <[email protected]> 0 siblings, 0 replies; 60+ messages in thread From: jian he @ 2025-03-31 07:26 UTC (permalink / raw) To: Peter Eisentraut <[email protected]>; +Cc: Álvaro Herrera <[email protected]>; Xuneng Zhou <[email protected]>; Navneet Kumar <[email protected]>; [email protected] On Fri, Mar 28, 2025 at 10:06 PM Peter Eisentraut <[email protected]> wrote: > > On 24.03.25 04:26, jian he wrote: > > rebase, and some minor code comments change. > > I have committed this. > In an earlier thread, I also posted a patch for supporting virtual generated columns over domain type. The code is somehow similar, so I post the remaining patch to this thread. v7-0001 we need to compute the generation expression for the domain with constraints, thus rename ExecComputeStoredGenerated to ExecComputeGenerated. v7-0002 soft error variant of ExecPrepareExpr, ExecInitExpr. for soft error processing of CoerceToDomain. we don't want error messages like "value for domain d2 violates check constraint "d2_check"" while validating existing domain data, we want something like: +ERROR: column "b" of table "gtest24" contains values that violate the new constraint v7-0003 supports virtual generation columns over domain type. If the domain has constraints then we need to compute the virtual generation expression, that happens mainly within ExecComputeGenerated. if a virtual generation column type is domain_with_constraint, then ALTER DOMAIN ADD CONSTRAINTS need to revalidate these virtual generation expressions again. so in validateDomainCheckConstraint, validateDomainNotNullConstraint We need to fetch the generation expression (build_generation_expression), compile the generation expression (ExecPrepareExprSafe), and evaluate it (ExecEvalExprSwitchContext). I also posted patch summary earlier at [1] [1] https://postgr.es/m/CACJufxHT4R1oABzeQuvjb6DHrig7k-QSr6LEe53Q_nLi9pfanA@mail.gmail.com Attachments: [text/x-patch] v7-0003-domain-over-virtual-generated-column.patch (32.8K, ../../CACJufxGwVqkPfyMfF08QTZuQLT+nWh8q8kcE57xrrzgixxRTEA@mail.gmail.com/2-v7-0003-domain-over-virtual-generated-column.patch) download | inline diff: From 346dbce94c008a1ec9447ca65c7b7fcd0f8428d6 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Mon, 31 Mar 2025 15:02:46 +0800 Subject: [PATCH v7 3/3] domain over virtual generated column. domains that don't have constraints work just fine. domain constraints check happen within ExecComputeGenerated. we compute the virtual generated column in ExecComputeGenerated and discarded the value. if value cannot coerce to domain then we will error out. domain_with_constaint can be element type of range, multirange, array, composite. to be bulletproof, if this column type is not type of TYPTYPE_BASE or it's an array type, then we do actually compute the generated expression. This can be have negative performance for INSERTs The following two query shows in pg_catalog, most of the system type is TYPTYPE_BASE. So I guess this compromise is fine. select count(*),typtype from pg_type where typnamespace = 11 group by 2; select typname, typrelid, pc.reltype, pc.oid, pt.oid from pg_type pt join pg_class pc on pc.oid = pt.typrelid where pt.typnamespace = 11 and pt.typtype = 'c' and pc.reltype = 0; ALTER DOMAIN ADD CONSTRAINT variant is supported. DOMAIN with default values are supported. but virtual generated column already have generated expression, so domain default expression doesn't matter. ALTER TABLE ADD VIRTUAL GENERATED COLUMN. need table scan to verify new column generation expression value satisfied the domain constraints. but no need table rewrite! discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/catalog/heap.c | 13 +- src/backend/commands/copyfrom.c | 5 +- src/backend/commands/tablecmds.c | 48 +++- src/backend/commands/typecmds.c | 209 +++++++++++++++--- src/backend/executor/nodeModifyTable.c | 88 ++++++-- src/include/catalog/heap.h | 1 - src/test/regress/expected/fast_default.out | 4 + .../regress/expected/generated_virtual.out | 65 +++++- src/test/regress/sql/fast_default.sql | 4 + src/test/regress/sql/generated_virtual.sql | 47 +++- 10 files changed, 398 insertions(+), 86 deletions(-) diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index b807ab66668..5519690d85c 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -508,7 +508,7 @@ CheckAttributeNamesTypes(TupleDesc tupdesc, char relkind, TupleDescAttr(tupdesc, i)->atttypid, TupleDescAttr(tupdesc, i)->attcollation, NIL, /* assume we're creating a new rowtype */ - flags | (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL ? CHKATYPE_IS_VIRTUAL : 0)); + flags); } } @@ -583,17 +583,6 @@ CheckAttributeType(const char *attname, } else if (att_typtype == TYPTYPE_DOMAIN) { - /* - * Prevent virtual generated columns from having a domain type. We - * would have to enforce domain constraints when columns underlying - * the generated column change. This could possibly be implemented, - * but it's not. - */ - if (flags & CHKATYPE_IS_VIRTUAL) - ereport(ERROR, - errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("virtual generated column \"%s\" cannot have a domain type", attname)); - /* * If it's a domain, recurse to check its base type. */ diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 906b6581e11..0086e4b2936 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1343,9 +1343,10 @@ CopyFrom(CopyFromState cstate) } else { - /* Compute stored generated columns */ + /* Compute generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && - resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) + (resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored || + resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, myslot, CMD_INSERT); diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 10624353b0a..4acae8d5568 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -5989,7 +5989,7 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode, * rebuild data. */ if (tab->constraints != NIL || tab->verify_new_notnull || - tab->partition_constraint != NULL) + tab->newvals || tab->partition_constraint != NULL) ATRewriteTable(tab, InvalidOid); /* @@ -6109,6 +6109,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) BulkInsertState bistate; int ti_options; ExprState *partqualstate = NULL; + List *domain_virtual_attrs = NIL; /* * Open the relation(s). We have surely already locked the existing @@ -6184,6 +6185,16 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) /* expr already planned */ ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL); + if (tab->rewrite == 0 && ex->is_generated) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, ex->attnum - 1); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL && + DomainHasConstraints(attr->atttypid)) + { + Assert(!attr->attisdropped); + domain_virtual_attrs = lappend_int(domain_virtual_attrs, attr->attnum); + } + } } notnull_attrs = notnull_virtual_attrs = NIL; @@ -6215,6 +6226,13 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) needscan = true; } + /* + * We need verify domain constraints on the virtual generated column are + * satisfied, which requires table scan. + */ + if (domain_virtual_attrs != NIL) + needscan = true; + if (newrel || needscan) { ExprContext *econtext; @@ -6473,6 +6491,34 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) } } + /* + * domain_virtual_attrs is list of newly added columns that is virtual + * generated column over domain with constraints. we need to check + * whether these domain constraints are satisfied. + */ + if (domain_virtual_attrs != NIL) + { + Assert(tab->rewrite == 0); + + foreach(l, tab->newvals) + { + NewColumnValue *ex = lfirst(l); + + if (!ex->is_generated) + continue; + + if(list_member_int(domain_virtual_attrs, ex->attnum) && + !ExecCheck(ex->exprstate, econtext)) + { + Form_pg_attribute attr = TupleDescAttr(newTupDesc, ex->attnum - 1); + ereport(ERROR, + errcode(ERRCODE_CHECK_VIOLATION), + errmsg("value for domain %s is violated by some row", + format_type_be(attr->atttypid))); + } + } + } + if (partqualstate && !ExecCheck(partqualstate, econtext)) { if (tab->validate_default) diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c index 3cb3ca1cca1..59c1dda5618 100644 --- a/src/backend/commands/typecmds.c +++ b/src/backend/commands/typecmds.c @@ -65,6 +65,7 @@ #include "parser/parse_expr.h" #include "parser/parse_func.h" #include "parser/parse_type.h" +#include "rewrite/rewriteHandler.h" #include "utils/builtins.h" #include "utils/fmgroids.h" #include "utils/inval.h" @@ -2772,6 +2773,8 @@ AlterDomainNotNull(List *names, bool notNull) typTup->typbasetype, typTup->typtypmod, constr, NameStr(typTup->typname), NULL); + CommandCounterIncrement(); + validateDomainNotNullConstraint(domainoid); } else @@ -2974,7 +2977,12 @@ AlterDomainAddConstraint(List *names, Node *newConstraint, * to. */ if (!constr->skip_validation) + { + /* need CCI, so we have fresh domain constraint info */ + CommandCounterIncrement(); + validateDomainCheckConstraint(domainoid, ccbin); + } /* * We must send out an sinval message for the domain, to ensure that @@ -2997,7 +3005,12 @@ AlterDomainAddConstraint(List *names, Node *newConstraint, constr, NameStr(typTup->typname), constrAddr); if (!constr->skip_validation) + { + /* need CCI, so we have fresh domain constraint info */ + CommandCounterIncrement(); + validateDomainNotNullConstraint(domainoid); + } typTup->typnotnull = true; CatalogTupleUpdate(typrel, &tup->t_self, tup); @@ -3121,6 +3134,13 @@ validateDomainNotNullConstraint(Oid domainoid) List *rels; ListCell *rt; + EState *estate; + ExprContext *econtext; + + /* we need EState for domain over virtual generated column */ + estate = CreateExecutorState(); + econtext = GetPerTupleExprContext(estate); + /* Fetch relation list with attributes based on this domain */ /* ShareLock is sufficient to prevent concurrent data changes */ @@ -3134,6 +3154,47 @@ validateDomainNotNullConstraint(Oid domainoid) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + Form_pg_attribute attr; + ExprState **ri_GeneratedExprs = NULL; + int attnum; + int count = 0; + + /* cacahe virtual generated columns handling */ + if (tupdesc->constr && tupdesc->constr->has_generated_virtual) + { + ri_GeneratedExprs = (ExprState **) palloc0(rtc->natts * sizeof(ExprState *)); + + /* + * We implement this by building a NullTest node for each virtual + * generated column, which we cache in ri_GeneratedExprs, and + * running those through ExecCheck() + */ + for (int i = 0; i < rtc->natts; i++) + { + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + NullTest *nnulltest; + + nnulltest = makeNode(NullTest); + nnulltest->arg = (Expr *) build_generation_expression(testrel, attnum);; + nnulltest->nulltesttype = IS_NOT_NULL; + nnulltest->argisrow = false; + nnulltest->location = -1; + + ri_GeneratedExprs[i] = ExecPrepareExpr((Expr *) nnulltest, estate); + count++; + } + } + } + if (count == 0 && ri_GeneratedExprs != NULL) + { + pfree(ri_GeneratedExprs); + ri_GeneratedExprs = NULL; + } + /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3146,8 +3207,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); if (slot_attisnull(slot, attnum)) { @@ -3158,14 +3219,30 @@ validateDomainNotNullConstraint(Oid domainoid) * only executes in an ALTER DOMAIN command, the client * should already know which domain is in question. */ - ereport(ERROR, - (errcode(ERRCODE_NOT_NULL_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains null values", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + if (attr->attgenerated != ATTRIBUTE_GENERATED_VIRTUAL) + ereport(ERROR, + (errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + else + { + econtext->ecxt_scantuple = slot; + Assert(ri_GeneratedExprs[i] != NULL); + + if (!ExecCheck(ri_GeneratedExprs[i] , econtext)) + ereport(ERROR, + errcode(ERRCODE_NOT_NULL_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains null values", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } } } + + ResetExprContext(econtext); } ExecDropSingleTupleTableSlot(slot); table_endscan(scan); @@ -3174,6 +3251,8 @@ validateDomainNotNullConstraint(Oid domainoid) /* Close each rel after processing, but keep lock */ table_close(testrel, NoLock); } + + FreeExecutorState(estate); } /* @@ -3210,6 +3289,41 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) TupleTableSlot *slot; TableScanDesc scan; Snapshot snapshot; + ExprState **ri_GeneratedExprs = NULL; + Form_pg_attribute attr; + int attnum; + int count = 0; + + /* cacahe virtual generated columns handling */ + if (tupdesc->constr && tupdesc->constr->has_generated_virtual) + { + ri_GeneratedExprs = (ExprState **) palloc0(rtc->natts * sizeof(ExprState *)); + for (int i = 0; i < rtc->natts; i++) + { + Expr *defexpr; + + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) + { + defexpr = (Expr *) build_generation_expression(testrel, attnum); + + /* + * we need evaluate defexpr error soft way, otherwise + * the evaulation failure error would be "value for domain + * violate check constraints", which is not helpful error + * message while validating domain check constraint. + */ + ri_GeneratedExprs[i] = ExecPrepareExprSafe(defexpr, estate); + count++; + } + } + } + if (count == 0 && ri_GeneratedExprs != NULL) + { + pfree(ri_GeneratedExprs); + ri_GeneratedExprs = NULL; + } /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); @@ -3222,37 +3336,68 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin) /* Test attributes that are of the domain */ for (i = 0; i < rtc->natts; i++) { - int attnum = rtc->atts[i]; Datum d; bool isNull; Datum conResult; - Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1); - d = slot_getattr(slot, attnum, &isNull); + attnum = rtc->atts[i]; + attr = TupleDescAttr(tupdesc, attnum - 1); - econtext->domainValue_datum = d; - econtext->domainValue_isNull = isNull; - - conResult = ExecEvalExprSwitchContext(exprstate, - econtext, - &isNull); - - if (!isNull && !DatumGetBool(conResult)) + if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL) { /* - * In principle the auxiliary information for this error - * should be errdomainconstraint(), but errtablecol() - * seems considerably more useful in practice. Since this - * code only executes in an ALTER DOMAIN command, the - * client should already know which domain is in question, - * and which constraint too. - */ - ereport(ERROR, - (errcode(ERRCODE_CHECK_VIOLATION), - errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", - NameStr(attr->attname), - RelationGetRelationName(testrel)), - errtablecol(testrel, attnum))); + * we'll use the EState's per-tuple context for evaluating + * domain check constraint associated with virtual generated + * column expressions (creating it if it's not already + * there). + */ + econtext = GetPerTupleExprContext(estate); + + /* Arrange for econtext's scan tuple to be the tuple under test */ + econtext->ecxt_scantuple = slot; + + conResult = ExecEvalExprSwitchContext(ri_GeneratedExprs[i], + econtext, + &isNull); + if (SOFT_ERROR_OCCURRED(ri_GeneratedExprs[i]->escontext)) + { + isNull = true; + ereport(ERROR, + errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum)); + } + } + else + { + d = slot_getattr(slot, attnum, &isNull); + + econtext->domainValue_datum = d; + econtext->domainValue_isNull = isNull; + + conResult = ExecEvalExprSwitchContext(exprstate, + econtext, + &isNull); + + if (!isNull && !DatumGetBool(conResult)) + { + /* + * In principle the auxiliary information for this error + * should be errdomainconstraint(), but errtablecol() + * seems considerably more useful in practice. Since this + * code only executes in an ALTER DOMAIN command, the + * client should already know which domain is in question, + * and which constraint too. + */ + ereport(ERROR, + (errcode(ERRCODE_CHECK_VIOLATION), + errmsg("column \"%s\" of table \"%s\" contains values that violate the new constraint", + NameStr(attr->attname), + RelationGetRelationName(testrel)), + errtablecol(testrel, attnum))); + } } } diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 5a581446c7d..7424dcf2742 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -67,6 +67,7 @@ #include "storage/lmgr.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/lsyscache.h" #include "utils/rel.h" #include "utils/snapmgr.h" @@ -395,7 +396,7 @@ ExecCheckTIDVisible(EState *estate, * * This fills the resultRelInfo's ri_GeneratedExprsI/ri_NumGeneratedNeededI or * ri_GeneratedExprsU/ri_NumGeneratedNeededU fields, depending on cmdtype. - * This is used only for stored generated columns. + * This is used for stored and virtual generated columns. * * If cmdType == CMD_UPDATE, the ri_extraUpdatedCols field is filled too. * This is used by both stored and virtual generated columns. @@ -477,6 +478,33 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); ri_NumGeneratedNeeded++; } + else + { + /* + * Virtual generated column only need to be computed when the + * type is domain_with_constraint. However, + * domain_with_constraint can be the element type of range, + * composite, or array. + * + * To determine whether the true element type is + * domain_with_constraint, multiple lookup_type_cache calls seems + * doable. However, this would add a lot of code. So simplify + * it: only when the type is TYPTYPE_BASE and not an array type, + * computation is not needed. + */ + Oid typelem = InvalidOid; + Oid atttypid = TupleDescAttr(tupdesc, i)->atttypid; + char att_typtype = get_typtype(atttypid); + + if (att_typtype == TYPTYPE_BASE) + typelem = get_element_type(atttypid); + + if (att_typtype != TYPTYPE_BASE || OidIsValid(typelem)) + { + ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate); + ri_NumGeneratedNeeded++; + } + } /* If UPDATE, mark column in resultRelInfo->ri_extraUpdatedCols */ if (cmdtype == CMD_UPDATE) @@ -518,7 +546,9 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, /* * Compute generated columns for a tuple. - * we might support virtual generated column in future, currently not. + * Generally, we don't need to compute virtual generated column, except for + * column type is domain with constraint. Since virtual generated column don't + * have storage, we don't need to store it. */ void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, @@ -534,7 +564,8 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, bool *nulls; /* We should not be called unless this is true */ - Assert(tupdesc->constr && tupdesc->constr->has_generated_stored); + Assert(tupdesc->constr); + Assert(tupdesc->constr->has_generated_stored || tupdesc->constr->has_generated_virtual); /* * Initialize the expressions if we didn't already, and check whether we @@ -552,11 +583,14 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, { if (resultRelInfo->ri_GeneratedExprsI == NULL) ExecInitGenerated(resultRelInfo, estate, cmdtype); - /* Early exit is impossible given the prior Assert */ - Assert(resultRelInfo->ri_NumGeneratedNeededI > 0); + if (resultRelInfo->ri_NumGeneratedNeededI == 0) + return; ri_GeneratedExprs = resultRelInfo->ri_GeneratedExprsI; } + if (ri_GeneratedExprs != NULL) + Assert(resultRelInfo->ri_NumGeneratedNeededU > 0 || resultRelInfo->ri_NumGeneratedNeededI > 0); + oldContext = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate)); values = palloc(sizeof(*values) * natts); @@ -567,28 +601,35 @@ ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, for (int i = 0; i < natts; i++) { - CompactAttribute *attr = TupleDescCompactAttr(tupdesc, i); + Form_pg_attribute attr = TupleDescAttr(tupdesc, i); if (ri_GeneratedExprs[i]) { Datum val; bool isnull; - Assert(TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED); - econtext->ecxt_scantuple = slot; val = ExecEvalExpr(ri_GeneratedExprs[i], econtext, &isnull); - /* - * We must make a copy of val as we have no guarantees about where - * memory for a pass-by-reference Datum is located. - */ - if (!isnull) - val = datumCopy(val, attr->attbyval, attr->attlen); + if (attr->attgenerated == ATTRIBUTE_GENERATED_STORED) + { + /* + * We must make a copy of val as we have no guarantees about where + * memory for a pass-by-reference Datum is located. + */ + if (!isnull) + val = datumCopy(val, attr->attbyval, attr->attlen); - values[i] = val; - nulls[i] = isnull; + values[i] = val; + nulls[i] = isnull; + } + else + { + Assert(attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL); + values[i] = (Datum) 0; + nulls[i] = true; + } } else { @@ -907,10 +948,11 @@ ExecInsert(ModifyTableContext *context, slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -1034,10 +1076,11 @@ ExecInsert(ModifyTableContext *context, slot->tts_tableOid = RelationGetRelid(resultRelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_INSERT); @@ -2122,10 +2165,11 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, slot->tts_tableOid = RelationGetRelid(resultRelationDesc); /* - * Compute stored generated columns + * Compute generated columns */ if (resultRelationDesc->rd_att->constr && - resultRelationDesc->rd_att->constr->has_generated_stored) + (resultRelationDesc->rd_att->constr->has_generated_stored || + resultRelationDesc->rd_att->constr->has_generated_virtual)) ExecComputeGenerated(resultRelInfo, estate, slot, CMD_UPDATE); } diff --git a/src/include/catalog/heap.h b/src/include/catalog/heap.h index dbd339e9df4..11c7f7afbfd 100644 --- a/src/include/catalog/heap.h +++ b/src/include/catalog/heap.h @@ -23,7 +23,6 @@ #define CHKATYPE_ANYARRAY 0x01 /* allow ANYARRAY */ #define CHKATYPE_ANYRECORD 0x02 /* allow RECORD and RECORD[] */ #define CHKATYPE_IS_PARTKEY 0x04 /* attname is part key # not column */ -#define CHKATYPE_IS_VIRTUAL 0x08 /* is virtual generated column */ typedef struct RawColumnDefault { diff --git a/src/test/regress/expected/fast_default.out b/src/test/regress/expected/fast_default.out index ccbcdf8403f..e1353560aba 100644 --- a/src/test/regress/expected/fast_default.out +++ b/src/test/regress/expected/fast_default.out @@ -70,6 +70,9 @@ NOTICE: rewriting table has_volatile for reason 4 -- stored generated columns need a rewrite ALTER TABLE has_volatile ADD col7 int GENERATED ALWAYS AS (55) stored; NOTICE: rewriting table has_volatile for reason 2 +-- virtual generated columns over volatile domain constraint don't need a rewrite +CREATE DOMAIN d1 as INT CHECK(value < random(min=>12::int, max=>21)); +ALTER TABLE has_volatile ADD col8 int GENERATED ALWAYS AS (1 + id) VIRTUAL; -- Test a large sample of different datatypes CREATE TABLE T(pk INT NOT NULL PRIMARY KEY, c_int INT DEFAULT 1); SELECT set('t'); @@ -922,6 +925,7 @@ DROP FUNCTION set(name); DROP FUNCTION comp(); DROP TABLE m; DROP TABLE has_volatile; +DROP DOMAIN d1; DROP EVENT TRIGGER has_volatile_rewrite; DROP FUNCTION log_rewrite; DROP SCHEMA fast_default; diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index 26bbe1e9c31..925c15caf5b 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -790,16 +790,63 @@ ERROR: relation "gtest23p" does not exist --INSERT INTO gtest23q VALUES (1, 2); -- ok --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +UPDATE gtest24 SET a = 6; -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +COPY gtest24 FROM stdin; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +CONTEXT: COPY gtest24, line 1: "6" +SELECT * FROM gtest24; + a | b +---+--- + 4 | 8 + 3 | 6 + | +(3 rows) + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ERROR: column "c" of relation "gtest24" contains null values +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +ERROR: column "b" of table "gtest24" contains null values +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ERROR: column "b" of table "gtest24" contains values that violate the new constraint +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); -ERROR: virtual generated column "b" cannot have a domain type ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +INSERT INTO gtest24r (a) VALUES (5); -- error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check2" +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +ERROR: value for domain gtestdomain1 violates check constraint "gtestdomain1_check" +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +ERROR: null value in column "c" of relation "gtest24v" violates not-null constraint +DETAIL: Failing row contains ({"a": [6, -1], "b": [6, 10]}, virtual, virtual). +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); CREATE TABLE gtest28 OF gtest_type (f1 WITH OPTIONS GENERATED ALWAYS AS (f2 *2) VIRTUAL); diff --git a/src/test/regress/sql/fast_default.sql b/src/test/regress/sql/fast_default.sql index 068dd0bc8aa..ffec1e11011 100644 --- a/src/test/regress/sql/fast_default.sql +++ b/src/test/regress/sql/fast_default.sql @@ -77,6 +77,9 @@ ALTER TABLE has_volatile ALTER COLUMN col1 SET DATA TYPE float8, -- stored generated columns need a rewrite ALTER TABLE has_volatile ADD col7 int GENERATED ALWAYS AS (55) stored; +-- virtual generated columns over volatile domain constraint don't need a rewrite +CREATE DOMAIN d1 as INT CHECK(value < random(min=>12::int, max=>21)); +ALTER TABLE has_volatile ADD col8 int GENERATED ALWAYS AS (1 + id) VIRTUAL; -- Test a large sample of different datatypes @@ -616,6 +619,7 @@ DROP FUNCTION set(name); DROP FUNCTION comp(); DROP TABLE m; DROP TABLE has_volatile; +DROP DOMAIN d1; DROP EVENT TRIGGER has_volatile_rewrite; DROP FUNCTION log_rewrite; DROP SCHEMA fast_default; diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index 13cfbd76859..383e20f67df 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -444,14 +444,47 @@ CREATE TABLE gtest23q (a int PRIMARY KEY, b int REFERENCES gtest23p (y)); --INSERT INTO gtest23q VALUES (2, 5); -- error -- domains -CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10); -CREATE TABLE gtest24 (a int PRIMARY KEY, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); ---INSERT INTO gtest24 (a) VALUES (4); -- ok ---INSERT INTO gtest24 (a) VALUES (6); -- error +CREATE DOMAIN gtestdomain1 AS int CHECK (VALUE < 10) DEFAULT 12; +CREATE TABLE gtest24 (a int UNIQUE, b gtestdomain1 GENERATED ALWAYS AS (a * 2) VIRTUAL); +INSERT INTO gtest24 (a, b) VALUES (4, default); -- ok +INSERT INTO gtest24 (a) VALUES (3), (NULL); -- ok +INSERT INTO gtest24 (a) VALUES (6); -- error +UPDATE gtest24 SET a = 6; -- error +COPY gtest24 FROM stdin; --error +6 +\. + +SELECT * FROM gtest24; + +--ALTER TABLE ADD COLUM variant. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual not null; --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 3) virtual check (c < 10); --error +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 4) virtual; --table rewrite then error. +ALTER TABLE gtest24 ADD COLUMN c gtestdomain1 GENERATED ALWAYS AS (a * 2) virtual; --ok + +--alter domain add constraint variant. +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NULL); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --error +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --error +DELETE FROM gtest24 WHERE a is NULL; +ALTER DOMAIN gtestdomain1 ADD NOT NULL; --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (value IS NOT NULL); --ok +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 7); --error +ALTER DOMAIN gtestdomain1 ADD CHECK (VALUE < 9); --ok + CREATE TYPE gtestdomain1range AS range (subtype = gtestdomain1); -CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 5)) VIRTUAL); ---INSERT INTO gtest24r (a) VALUES (4); -- ok ---INSERT INTO gtest24r (a) VALUES (6); -- error +CREATE TABLE gtest24r (a int PRIMARY KEY, b gtestdomain1range GENERATED ALWAYS AS (gtestdomain1range(a, a + 4)) VIRTUAL); +INSERT INTO gtest24r (a) VALUES (4); -- ok +INSERT INTO gtest24r (a) VALUES (6); -- error +INSERT INTO gtest24r (a) VALUES (5); -- error + +CREATE TABLE gtest24v ( + a jsonb, + b gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.a' returning gtestdomain1[] error on error)) VIRTUAL, + c gtestdomain1[] GENERATED ALWAYS AS (JSON_QUERY(a, '$.b' returning gtestdomain1[])) VIRTUAL not null); +insert into gtest24v select jsonb '{"a":[6,10], "b":[6,2]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,10]}'; --error +insert into gtest24v select jsonb '{"a":[6,-1], "b":[6,2]}'; --ok -- typed tables (currently not supported) CREATE TYPE gtest_type AS (f1 integer, f2 text, f3 bigint); -- 2.34.1 [text/x-patch] v7-0002-soft-error-variant-of-ExecPrepareExpr-ExecInitExp.patch (3.9K, ../../CACJufxGwVqkPfyMfF08QTZuQLT+nWh8q8kcE57xrrzgixxRTEA@mail.gmail.com/3-v7-0002-soft-error-variant-of-ExecPrepareExpr-ExecInitExp.patch) download | inline diff: From c93dddb0c9e744fd4e8a329a6d28413137c6dd83 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 13 Mar 2025 15:05:41 +0800 Subject: [PATCH v7 2/3] soft error variant of ExecPrepareExpr, ExecInitExpr ExecPrepareExprSafe and ExecInitExprSafe. ExecPrepareExprSafe initialize for expression execution with soft error support. not all expression node support it. some like CoerceToDomain do support it. XXX more comments. discussion: https://postgr.es/m/CACJufxE_+iZBR1i49k_AHigppPwLTJi6km8NOsC7FWvKdEmmXg@mail.gmail.com --- src/backend/executor/execExpr.c | 63 +++++++++++++++++++++++++++++++++ src/include/executor/executor.h | 2 ++ 2 files changed, 65 insertions(+) diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c index f1569879b52..b8f5f647281 100644 --- a/src/backend/executor/execExpr.c +++ b/src/backend/executor/execExpr.c @@ -170,6 +170,46 @@ ExecInitExpr(Expr *node, PlanState *parent) return state; } +/* + * ExecInitExpr: soft error variant of ExecInitExpr. + * use it only for expression nodes support soft errors, not all expression + * nodes support it. +*/ +ExprState * +ExecInitExprSafe(Expr *node, PlanState *parent) +{ + ExprState *state; + ExprEvalStep scratch = {0}; + + /* Special case: NULL expression produces a NULL ExprState pointer */ + if (node == NULL) + return NULL; + + /* Initialize ExprState with empty step list */ + state = makeNode(ExprState); + state->expr = node; + state->parent = parent; + state->ext_params = NULL; + state->escontext = makeNode(ErrorSaveContext); + state->escontext->type = T_ErrorSaveContext; + state->escontext->error_occurred = false; + state->escontext->details_wanted = true; + + /* Insert setup steps as needed */ + ExecCreateExprSetupSteps(state, (Node *) node); + + /* Compile the expression proper */ + ExecInitExprRec(node, state, &state->resvalue, &state->resnull); + + /* Finally, append a DONE step */ + scratch.opcode = EEOP_DONE_RETURN; + ExprEvalPushStep(state, &scratch); + + ExecReadyExpr(state); + + return state; +} + /* * ExecInitExprWithParams: prepare a standalone expression tree for execution * @@ -778,6 +818,29 @@ ExecPrepareExpr(Expr *node, EState *estate) return result; } +/* + * ExecPrepareExprSafe: soft error variant of ExecPrepareExpr. + * + * use it when expression node *support* soft error expression execution. + * ExecPrepareExpr comments apply to here too. + */ +ExprState * +ExecPrepareExprSafe(Expr *node, EState *estate) +{ + ExprState *result; + MemoryContext oldcontext; + + oldcontext = MemoryContextSwitchTo(estate->es_query_cxt); + + node = expression_planner(node); + + result = ExecInitExprSafe(node, NULL); + + MemoryContextSwitchTo(oldcontext); + + return result; +} + /* * ExecPrepareQual --- initialize for qual execution outside a normal * Plan tree context. diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index ae99407db89..a26160042ee 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -346,6 +346,7 @@ ExecProcNode(PlanState *node) * prototypes from functions in execExpr.c */ extern ExprState *ExecInitExpr(Expr *node, PlanState *parent); +extern ExprState *ExecInitExprSafe(Expr *node, PlanState *parent); extern ExprState *ExecInitExprWithParams(Expr *node, ParamListInfo ext_params); extern ExprState *ExecInitQual(List *qual, PlanState *parent); extern ExprState *ExecInitCheck(List *qual, PlanState *parent); @@ -394,6 +395,7 @@ extern ProjectionInfo *ExecBuildUpdateProjection(List *targetList, TupleTableSlot *slot, PlanState *parent); extern ExprState *ExecPrepareExpr(Expr *node, EState *estate); +extern ExprState *ExecPrepareExprSafe(Expr *node, EState *estate); extern ExprState *ExecPrepareQual(List *qual, EState *estate); extern ExprState *ExecPrepareCheck(List *qual, EState *estate); extern List *ExecPrepareExprList(List *nodes, EState *estate); -- 2.34.1 [text/x-patch] v7-0001-rename-ExecComputeStoredGenerated-to-ExecComputeG.patch (5.2K, ../../CACJufxGwVqkPfyMfF08QTZuQLT+nWh8q8kcE57xrrzgixxRTEA@mail.gmail.com/4-v7-0001-rename-ExecComputeStoredGenerated-to-ExecComputeG.patch) download | inline diff: From 28a05de321046b578686cc4e4802bcd4243d5343 Mon Sep 17 00:00:00 2001 From: jian he <[email protected]> Date: Thu, 13 Mar 2025 20:15:46 +0800 Subject: [PATCH v7 1/3] rename ExecComputeStoredGenerated to ExecComputeGenerated to support virtual generated column over domain type, we actually need compute the virtual generated expression. we did it at ExecComputeGenerated for stored, we can use it for virtual. so do the rename. discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com --- src/backend/commands/copyfrom.c | 4 ++-- src/backend/executor/execReplication.c | 8 ++++---- src/backend/executor/nodeModifyTable.c | 20 ++++++++++---------- src/include/executor/nodeModifyTable.h | 5 ++--- 4 files changed, 18 insertions(+), 19 deletions(-) diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index fbbbc09a97b..906b6581e11 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1346,8 +1346,8 @@ CopyFrom(CopyFromState cstate) /* Compute stored generated columns */ if (resultRelInfo->ri_RelationDesc->rd_att->constr && resultRelInfo->ri_RelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, myslot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, myslot, + CMD_INSERT); /* * If the target is a plain table, check the constraints of diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c index ede89ea3cf9..40c078638ab 100644 --- a/src/backend/executor/execReplication.c +++ b/src/backend/executor/execReplication.c @@ -557,8 +557,8 @@ ExecSimpleRelationInsert(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* Check the constraints of the tuple */ if (rel->rd_att->constr) @@ -654,8 +654,8 @@ ExecSimpleRelationUpdate(ResultRelInfo *resultRelInfo, /* Compute stored generated columns */ if (rel->rd_att->constr && rel->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); /* Check the constraints of the tuple */ if (rel->rd_att->constr) diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 309e27f8b5f..5a581446c7d 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -517,12 +517,12 @@ ExecInitGenerated(ResultRelInfo *resultRelInfo, } /* - * Compute stored generated columns for a tuple + * Compute generated columns for a tuple. + * we might support virtual generated column in future, currently not. */ void -ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype) +ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot, CmdType cmdtype) { Relation rel = resultRelInfo->ri_RelationDesc; TupleDesc tupdesc = RelationGetDescr(rel); @@ -911,8 +911,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * If the FDW supports batching, and batching is requested, accumulate @@ -1038,8 +1038,8 @@ ExecInsert(ModifyTableContext *context, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_INSERT); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_INSERT); /* * Check any RLS WITH CHECK policies. @@ -2126,8 +2126,8 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo, */ if (resultRelationDesc->rd_att->constr && resultRelationDesc->rd_att->constr->has_generated_stored) - ExecComputeStoredGenerated(resultRelInfo, estate, slot, - CMD_UPDATE); + ExecComputeGenerated(resultRelInfo, estate, slot, + CMD_UPDATE); } /* diff --git a/src/include/executor/nodeModifyTable.h b/src/include/executor/nodeModifyTable.h index bf3b592e28f..de374c46d3c 100644 --- a/src/include/executor/nodeModifyTable.h +++ b/src/include/executor/nodeModifyTable.h @@ -19,9 +19,8 @@ extern void ExecInitGenerated(ResultRelInfo *resultRelInfo, EState *estate, CmdType cmdtype); -extern void ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo, - EState *estate, TupleTableSlot *slot, - CmdType cmdtype); +extern void ExecComputeGenerated(ResultRelInfo *resultRelInfo, EState *estate, + TupleTableSlot *slot,CmdType cmdtype); extern ModifyTableState *ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags); extern void ExecEndModifyTable(ModifyTableState *node); -- 2.34.1 ^ permalink raw reply [nested|flat] 60+ messages in thread
end of thread, other threads:[~2025-03-31 07:26 UTC | newest] Thread overview: 60+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v3 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v1 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v7 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v4 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v2 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v6 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2017-10-19 08:24 [PATCH v5 3/3] async postgres_fdw Kyotaro Horiguchi <[email protected]> 2025-02-10 13:33 support virtual generated column not null constraint jian he <[email protected]> 2025-02-26 07:00 ` Re: support virtual generated column not null constraint ego alter <[email protected]> 2025-03-06 13:44 ` Re: support virtual generated column not null constraint jian he <[email protected]> 2025-03-07 16:47 ` Re: support virtual generated column not null constraint Navneet Kumar <[email protected]> 2025-03-07 18:09 ` Re: support virtual generated column not null constraint Navneet Kumar <[email protected]> 2025-03-08 04:30 ` Re: support virtual generated column not null constraint Xuneng Zhou <[email protected]> 2025-03-08 10:10 ` Re: support virtual generated column not null constraint jian he <[email protected]> 2025-03-13 12:22 ` Re: support virtual generated column not null constraint jian he <[email protected]> 2025-03-19 16:19 ` Re: support virtual generated column not null constraint Álvaro Herrera <[email protected]> 2025-03-20 05:18 ` Re: support virtual generated column not null constraint jian he <[email protected]> 2025-03-21 04:33 ` Re: support virtual generated column not null constraint Xuneng Zhou <[email protected]> 2025-03-21 10:18 ` Re: support virtual generated column not null constraint Álvaro Herrera <[email protected]> 2025-03-24 03:26 ` Re: support virtual generated column not null constraint jian he <[email protected]> 2025-03-28 14:06 ` Re: support virtual generated column not null constraint Peter Eisentraut <[email protected]> 2025-03-31 07:26 ` Re: support virtual generated column not null constraint jian he <[email protected]> 2025-03-08 04:23 ` Re: support virtual generated column not null constraint Xuneng Zhou <[email protected]>
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