($INBOX_DIR/description missing)
help / color / mirror / Atom feedFrom: Kyotaro Horiguchi <[email protected]>
Subject: [PATCH 3/4] Add infrastructure to WAL-logging skip feature
Date: Thu, 11 Oct 2018 16:00:44 +0900
We used to optimize WAL-logging for truncation of in-transaction
crated tables in minimal mode by just singaling by
HEAP_INSERT_SKIP_WAL option on heap operations. This mechanism can
emit WAL records that results in corrupt state for certain series of
in-transaction operations. This patch provides infrastructure to track
pending at-comit fsyncs for a relation and in-transaction truncations.
heap_register_sync() should be used to start tracking before batch
operations like COPY and CLUSTER, and use BufferNeedsWAL() instead of
RelationNeedsWAL() at the places related to WAL-logging about
heap-modifying operations.
---
src/backend/access/heap/heapam.c | 31 ++++
src/backend/access/transam/xact.c | 7 +
src/backend/catalog/storage.c | 317 +++++++++++++++++++++++++++++++++---
src/backend/commands/tablecmds.c | 3 +-
src/backend/storage/buffer/bufmgr.c | 40 ++++-
src/backend/utils/cache/relcache.c | 13 ++
src/include/access/heapam.h | 1 +
src/include/catalog/storage.h | 5 +-
src/include/storage/bufmgr.h | 2 +
src/include/utils/rel.h | 8 +
10 files changed, 395 insertions(+), 32 deletions(-)
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index dc3499349b..5ea5ff5848 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -50,6 +50,7 @@
#include "access/xloginsert.h"
#include "access/xlogutils.h"
#include "catalog/catalog.h"
+#include "catalog/storage.h"
#include "miscadmin.h"
#include "pgstat.h"
#include "port/atomics.h"
@@ -9079,3 +9080,33 @@ heap_mask(char *pagedata, BlockNumber blkno)
}
}
}
+
+/*
+ * heap_register_sync - register a heap to be synced to disk at commit
+ *
+ * This can be used to skip WAL-logging changes on a relation file that has
+ * been created in the same transaction. This makes note of the current size of
+ * the relation, and ensures that when the relation is extended, any changes
+ * to the new blocks in the heap, in the same transaction, will not be
+ * WAL-logged. Instead, the heap contents are flushed to disk at commit,
+ * like heap_sync() does.
+ *
+ * This does the same for the TOAST heap, if any. Indexes are not affected.
+ */
+void
+heap_register_sync(Relation rel)
+{
+ /* non-WAL-logged tables never need fsync */
+ if (!RelationNeedsWAL(rel))
+ return;
+
+ RecordPendingSync(rel);
+ if (OidIsValid(rel->rd_rel->reltoastrelid))
+ {
+ Relation toastrel;
+
+ toastrel = heap_open(rel->rd_rel->reltoastrelid, AccessShareLock);
+ RecordPendingSync(toastrel);
+ heap_close(toastrel, AccessShareLock);
+ }
+}
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index e93262975d..6d62d6e34f 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -2021,6 +2021,9 @@ CommitTransaction(void)
/* close large objects before lower-level cleanup */
AtEOXact_LargeObject(true);
+ /* Flush updates to relations that we didn't WAL-logged */
+ smgrDoPendingSyncs(true);
+
/*
* Mark serializable transaction as complete for predicate locking
* purposes. This should be done as late as we can put it and still allow
@@ -2250,6 +2253,9 @@ PrepareTransaction(void)
/* close large objects before lower-level cleanup */
AtEOXact_LargeObject(true);
+ /* Flush updates to relations that we didn't WAL-logged */
+ smgrDoPendingSyncs(true);
+
/*
* Mark serializable transaction as complete for predicate locking
* purposes. This should be done as late as we can put it and still allow
@@ -2575,6 +2581,7 @@ AbortTransaction(void)
AtAbort_Notify();
AtEOXact_RelationMap(false, is_parallel_worker);
AtAbort_Twophase();
+ smgrDoPendingSyncs(false); /* abandone pending syncs */
/*
* Advertise the fact that we aborted in pg_xact (assuming that we got as
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index 0302507e6f..26dc3ddb1b 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -28,6 +28,7 @@
#include "catalog/storage_xlog.h"
#include "storage/freespace.h"
#include "storage/smgr.h"
+#include "utils/hsearch.h"
#include "utils/memutils.h"
#include "utils/rel.h"
@@ -62,6 +63,49 @@ typedef struct PendingRelDelete
static PendingRelDelete *pendingDeletes = NULL; /* head of linked list */
+/*
+ * We also track relation files (RelFileNode values) that have been created
+ * in the same transaction, and that have been modified without WAL-logging
+ * the action (an optimization possible with wal_level=minimal). When we are
+ * about to skip WAL-logging, a PendingRelSync entry is created, and
+ * 'sync_above' is set to the current size of the relation. Any operations
+ * on blocks < sync_above need to be WAL-logged as usual, but for operations
+ * on higher blocks, WAL-logging is skipped.
+ *
+ * NB: after WAL-logging has been skipped for a block, we must not WAL-log
+ * any subsequent actions on the same block either. Replaying the WAL record
+ * of the subsequent action might fail otherwise, as the "before" state of
+ * the block might not match, as the earlier actions were not WAL-logged.
+ * Likewise, after we have WAL-logged an operation for a block, we must
+ * WAL-log any subsequent operations on the same page as well. Replaying
+ * a possible full-page-image from the earlier WAL record would otherwise
+ * revert the page to the old state, even if we sync the relation at end
+ * of transaction.
+ *
+ * If a relation is truncated (without creating a new relfilenode), and we
+ * emit a WAL record of the truncation, we can't skip WAL-logging for any
+ * of the truncated blocks anymore, as replaying the truncation record will
+ * destroy all the data inserted after that. But if we have already decided
+ * to skip WAL-logging changes to a relation, and the relation is truncated,
+ * we don't need to WAL-log the truncation either.
+ *
+ * This mechanism is currently only used by heaps. Indexes are always
+ * WAL-logged. Also, this only applies for wal_level=minimal; with higher
+ * WAL levels we need the WAL for PITR/replication anyway.
+ */
+typedef struct PendingRelSync
+{
+ RelFileNode relnode; /* relation created in same xact */
+ BlockNumber sync_above; /* WAL-logging skipped for blocks >=
+ * sync_above */
+ BlockNumber truncated_to; /* truncation WAL record was written */
+} PendingRelSync;
+
+/* Relations that need to be fsync'd at commit */
+static HTAB *pendingSyncs = NULL;
+
+static PendingRelSync *getPendingSyncEntry(Relation rel, bool create);
+
/*
* RelationCreateStorage
* Create physical storage for a relation.
@@ -259,37 +303,117 @@ RelationTruncate(Relation rel, BlockNumber nblocks)
*/
if (RelationNeedsWAL(rel))
{
- /*
- * Make an XLOG entry reporting the file truncation.
- */
- XLogRecPtr lsn;
- xl_smgr_truncate xlrec;
+ PendingRelSync *pending_sync;
- xlrec.blkno = nblocks;
- xlrec.rnode = rel->rd_node;
- xlrec.flags = SMGR_TRUNCATE_ALL;
+ /* get pending sync entry, create if not yet */
+ pending_sync = getPendingSyncEntry(rel, true);
- XLogBeginInsert();
- XLogRegisterData((char *) &xlrec, sizeof(xlrec));
+ if (pending_sync->sync_above == InvalidBlockNumber ||
+ pending_sync->sync_above < nblocks)
+ {
+ /*
+ * This is the first time truncation of this relation in this
+ * transaction or truncation that leaves pages that need at-commit
+ * fsync. Make an XLOG entry reporting the file truncation.
+ */
+ XLogRecPtr lsn;
+ xl_smgr_truncate xlrec;
- lsn = XLogInsert(RM_SMGR_ID,
- XLOG_SMGR_TRUNCATE | XLR_SPECIAL_REL_UPDATE);
+ xlrec.blkno = nblocks;
+ xlrec.rnode = rel->rd_node;
+ xlrec.flags = SMGR_TRUNCATE_ALL;
- /*
- * Flush, because otherwise the truncation of the main relation might
- * hit the disk before the WAL record, and the truncation of the FSM
- * or visibility map. If we crashed during that window, we'd be left
- * with a truncated heap, but the FSM or visibility map would still
- * contain entries for the non-existent heap pages.
- */
- if (fsm || vm)
- XLogFlush(lsn);
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, sizeof(xlrec));
+
+ lsn = XLogInsert(RM_SMGR_ID,
+ XLOG_SMGR_TRUNCATE | XLR_SPECIAL_REL_UPDATE);
+
+ elog(DEBUG2, "WAL-logged truncation of rel %u/%u/%u to %u blocks",
+ rel->rd_node.spcNode, rel->rd_node.dbNode, rel->rd_node.relNode,
+ nblocks);
+
+ /*
+ * Flush, because otherwise the truncation of the main relation
+ * might hit the disk before the WAL record, and the truncation of
+ * the FSM or visibility map. If we crashed during that window,
+ * we'd be left with a truncated heap, but the FSM or visibility
+ * map would still contain entries for the non-existent heap
+ * pages.
+ */
+ if (fsm || vm)
+ XLogFlush(lsn);
+
+ rel->pending_sync->truncated_to = nblocks;
+ }
}
/* Do the real work */
smgrtruncate(rel->rd_smgr, MAIN_FORKNUM, nblocks);
}
+/*
+ * getPendingSyncEntry: get pendig sync entry.
+ *
+ * Returns pending sync entry for the relation. The entry tracks pending
+ * at-commit fsyncs for the relation. Creates one if needed when create is
+ * true.
+ */
+static PendingRelSync *
+getPendingSyncEntry(Relation rel, bool create)
+{
+ PendingRelSync *pendsync_entry = NULL;
+ bool found;
+
+ if (rel->pending_sync)
+ return rel->pending_sync;
+
+ /* we know we don't have pending sync entry */
+ if (!create && rel->no_pending_sync)
+ return NULL;
+
+ if (!pendingSyncs)
+ {
+ /* First time through: initialize the hash table */
+ HASHCTL ctl;
+
+ if (!create)
+ return NULL;
+
+ MemSet(&ctl, 0, sizeof(ctl));
+ ctl.keysize = sizeof(RelFileNode);
+ ctl.entrysize = sizeof(PendingRelSync);
+ ctl.hash = tag_hash;
+ pendingSyncs = hash_create("pending relation sync table", 5,
+ &ctl, HASH_ELEM | HASH_FUNCTION);
+ }
+
+ elog(DEBUG2, "getPendingSyncEntry: accessing hash for %d",
+ rel->rd_node.relNode);
+ pendsync_entry = (PendingRelSync *)
+ hash_search(pendingSyncs, (void *) &rel->rd_node,
+ create ? HASH_ENTER: HASH_FIND, &found);
+
+ if (!pendsync_entry)
+ {
+ rel->no_pending_sync = true;
+ return NULL;
+ }
+
+ /* new entry created */
+ if (!found)
+ {
+ pendsync_entry->truncated_to = InvalidBlockNumber;
+ pendsync_entry->sync_above = InvalidBlockNumber;
+ }
+
+ /* hold shortcut in Relation */
+ rel->no_pending_sync = false;
+ rel->pending_sync = pendsync_entry;
+
+ return pendsync_entry;
+}
+
/*
* smgrDoPendingDeletes() -- Take care of relation deletes at end of xact.
*
@@ -367,6 +491,24 @@ smgrDoPendingDeletes(bool isCommit)
}
}
+/*
+ * RelationRemovePendingSync() -- remove pendingSync entry for a relation
+ */
+void
+RelationRemovePendingSync(Relation rel)
+{
+ bool found;
+
+ rel->pending_sync = NULL;
+ rel->no_pending_sync = true;
+ if (pendingSyncs)
+ {
+ elog(DEBUG2, "RelationRemovePendingSync: accessing hash");
+ hash_search(pendingSyncs, (void *) &rel->rd_node, HASH_REMOVE, &found);
+ }
+}
+
+
/*
* smgrGetPendingDeletes() -- Get a list of non-temp relations to be deleted.
*
@@ -418,6 +560,139 @@ smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr)
return nrels;
}
+
+/*
+ * Remember that the given relation needs to be sync'd at commit, because we
+ * are going to skip WAL-logging subsequent actions to it.
+ */
+void
+RecordPendingSync(Relation rel)
+{
+ BlockNumber nblocks;
+ PendingRelSync *pending_sync;
+
+ Assert(RelationNeedsWAL(rel));
+
+ /* get pending sync entry, create if not yet */
+ pending_sync = getPendingSyncEntry(rel, true);
+
+ nblocks = RelationGetNumberOfBlocks(rel);
+
+ if (pending_sync->sync_above != InvalidBlockNumber)
+ {
+ elog(DEBUG2,
+ "pending sync for rel %u/%u/%u was already registered at block %u (new %u)",
+ rel->rd_node.spcNode, rel->rd_node.dbNode, rel->rd_node.relNode,
+ rel->pending_sync->sync_above, nblocks);
+
+ return;
+ }
+
+ elog(DEBUG2,
+ "registering new pending sync for rel %u/%u/%u at block %u",
+ rel->rd_node.spcNode, rel->rd_node.dbNode, rel->rd_node.relNode,
+ nblocks);
+ pending_sync->sync_above = nblocks;
+}
+
+/*
+ * Do changes to given heap page need to be WAL-logged?
+ *
+ * This takes into account any previous RecordPendingSync() requests.
+ *
+ * Note that it is required to check this before creating any WAL records for
+ * heap pages - it is not merely an optimization! WAL-logging a record, when
+ * we have already skipped a previous WAL record for the same page could lead
+ * to failure at WAL replay, as the "before" state expected by the record
+ * might not match what's on disk. Also, if the heap was truncated earlier, we
+ * must WAL-log any changes to the once-truncated blocks, because replaying
+ * the truncation record will destroy them.
+ */
+bool
+BufferNeedsWAL(Relation rel, Buffer buf)
+{
+ BlockNumber blkno = InvalidBlockNumber;
+ PendingRelSync *pending_sync;
+
+ if (!RelationNeedsWAL(rel))
+ return false;
+
+ /* fetch exising pending sync entry */
+ pending_sync = getPendingSyncEntry(rel, false);
+
+ /*
+ * no point in doing further work if we know that we don't have pending
+ * sync
+ */
+ if (!pending_sync)
+ return true;
+
+ Assert(BufferIsValid(buf));
+
+ blkno = BufferGetBlockNumber(buf);
+
+ /* we don't skip WAL-logging for pages that already done */
+ if (pending_sync->sync_above == InvalidBlockNumber ||
+ pending_sync->sync_above > blkno)
+ {
+ elog(DEBUG2, "not skipping WAL-logging for rel %u/%u/%u block %u, because sync_above is %u",
+ rel->rd_node.spcNode, rel->rd_node.dbNode, rel->rd_node.relNode,
+ blkno, rel->pending_sync->sync_above);
+ return true;
+ }
+
+ /*
+ * We have emitted a truncation record for this block.
+ */
+ if (pending_sync->truncated_to != InvalidBlockNumber &&
+ pending_sync->truncated_to <= blkno)
+ {
+ elog(DEBUG2, "not skipping WAL-logging for rel %u/%u/%u block %u, because it was truncated earlier in the same xact",
+ rel->rd_node.spcNode, rel->rd_node.dbNode, rel->rd_node.relNode,
+ blkno);
+ return true;
+ }
+
+ elog(DEBUG2, "skipping WAL-logging for rel %u/%u/%u block %u",
+ rel->rd_node.spcNode, rel->rd_node.dbNode, rel->rd_node.relNode,
+ blkno);
+
+ return false;
+}
+
+/*
+ * Sync to disk any relations that we skipped WAL-logging for earlier.
+ */
+void
+smgrDoPendingSyncs(bool isCommit)
+{
+ if (!pendingSyncs)
+ return;
+
+ if (isCommit)
+ {
+ HASH_SEQ_STATUS status;
+ PendingRelSync *pending;
+
+ hash_seq_init(&status, pendingSyncs);
+
+ while ((pending = hash_seq_search(&status)) != NULL)
+ {
+ if (pending->sync_above != InvalidBlockNumber)
+ {
+ FlushRelationBuffersWithoutRelCache(pending->relnode, false);
+ smgrimmedsync(smgropen(pending->relnode, InvalidBackendId), MAIN_FORKNUM);
+
+ elog(DEBUG2, "syncing rel %u/%u/%u", pending->relnode.spcNode,
+ pending->relnode.dbNode, pending->relnode.relNode);
+ }
+ }
+ }
+
+ hash_destroy(pendingSyncs);
+ pendingSyncs = NULL;
+}
+
/*
* PostPrepare_smgr -- Clean up after a successful PREPARE
*
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index a93b13c2fe..6190b3f605 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -11412,11 +11412,12 @@ ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode)
/*
* Create and copy all forks of the relation, and schedule unlinking of
- * old physical files.
+ * old physical files. Pending syncs for the old node is no longer needed.
*
* NOTE: any conflict in relfilenode value will be caught in
* RelationCreateStorage().
*/
+ RelationRemovePendingSync(rel);
RelationCreateStorage(newrnode, rel->rd_rel->relpersistence);
/* copy main fork */
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 273e2f385f..a9741f138c 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -451,6 +451,7 @@ static BufferDesc *BufferAlloc(SMgrRelation smgr,
BufferAccessStrategy strategy,
bool *foundPtr);
static void FlushBuffer(BufferDesc *buf, SMgrRelation reln);
+static void FlushRelationBuffers_common(SMgrRelation smgr, bool islocal);
static void AtProcExit_Buffers(int code, Datum arg);
static void CheckForBufferLeaks(void);
static int rnode_comparator(const void *p1, const void *p2);
@@ -3153,20 +3154,41 @@ PrintPinnedBufs(void)
void
FlushRelationBuffers(Relation rel)
{
- int i;
- BufferDesc *bufHdr;
-
/* Open rel at the smgr level if not already done */
RelationOpenSmgr(rel);
- if (RelationUsesLocalBuffers(rel))
+ FlushRelationBuffers_common(rel->rd_smgr, RelationUsesLocalBuffers(rel));
+}
+
+/*
+ * Like FlushRelationBuffers(), but the relation is specified by a
+ * RelFileNode
+ */
+void
+FlushRelationBuffersWithoutRelCache(RelFileNode rnode, bool islocal)
+{
+ FlushRelationBuffers_common(smgropen(rnode, InvalidBackendId), islocal);
+}
+
+/*
+ * Code shared between functions FlushRelationBuffers() and
+ * FlushRelationBuffersWithoutRelCache().
+ */
+static void
+FlushRelationBuffers_common(SMgrRelation smgr, bool islocal)
+{
+ RelFileNode rnode = smgr->smgr_rnode.node;
+ int i;
+ BufferDesc *bufHdr;
+
+ if (islocal)
{
for (i = 0; i < NLocBuffer; i++)
{
uint32 buf_state;
bufHdr = GetLocalBufferDescriptor(i);
- if (RelFileNodeEquals(bufHdr->tag.rnode, rel->rd_node) &&
+ if (RelFileNodeEquals(bufHdr->tag.rnode, rnode) &&
((buf_state = pg_atomic_read_u32(&bufHdr->state)) &
(BM_VALID | BM_DIRTY)) == (BM_VALID | BM_DIRTY))
{
@@ -3183,7 +3205,7 @@ FlushRelationBuffers(Relation rel)
PageSetChecksumInplace(localpage, bufHdr->tag.blockNum);
- smgrwrite(rel->rd_smgr,
+ smgrwrite(smgr,
bufHdr->tag.forkNum,
bufHdr->tag.blockNum,
localpage,
@@ -3213,18 +3235,18 @@ FlushRelationBuffers(Relation rel)
* As in DropRelFileNodeBuffers, an unlocked precheck should be safe
* and saves some cycles.
*/
- if (!RelFileNodeEquals(bufHdr->tag.rnode, rel->rd_node))
+ if (!RelFileNodeEquals(bufHdr->tag.rnode, rnode))
continue;
ReservePrivateRefCountEntry();
buf_state = LockBufHdr(bufHdr);
- if (RelFileNodeEquals(bufHdr->tag.rnode, rel->rd_node) &&
+ if (RelFileNodeEquals(bufHdr->tag.rnode, rnode) &&
(buf_state & (BM_VALID | BM_DIRTY)) == (BM_VALID | BM_DIRTY))
{
PinBuffer_Locked(bufHdr);
LWLockAcquire(BufferDescriptorGetContentLock(bufHdr), LW_SHARED);
- FlushBuffer(bufHdr, rel->rd_smgr);
+ FlushBuffer(bufHdr, smgr);
LWLockRelease(BufferDescriptorGetContentLock(bufHdr));
UnpinBuffer(bufHdr, true);
}
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 54a40ef00b..b5baa430db 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -75,6 +75,7 @@
#include "partitioning/partdesc.h"
#include "rewrite/rewriteDefine.h"
#include "rewrite/rowsecurity.h"
+#include "storage/bufmgr.h"
#include "storage/lmgr.h"
#include "storage/smgr.h"
#include "utils/array.h"
@@ -412,6 +413,10 @@ AllocateRelationDesc(Form_pg_class relp)
/* which we mark as a reference-counted tupdesc */
relation->rd_att->tdrefcount = 1;
+ /* We don't know if pending sync for this relation exists so far */
+ relation->pending_sync = NULL;
+ relation->no_pending_sync = false;
+
MemoryContextSwitchTo(oldcxt);
return relation;
@@ -1813,6 +1818,10 @@ formrdesc(const char *relationName, Oid relationReltype,
relation->rd_rel->relhasindex = true;
}
+ /* We don't know if pending sync for this relation exists so far */
+ relation->pending_sync = NULL;
+ relation->no_pending_sync = false;
+
/*
* add new reldesc to relcache
*/
@@ -3207,6 +3216,10 @@ RelationBuildLocalRelation(const char *relname,
else
rel->rd_rel->relfilenode = relfilenode;
+ /* newly built relation has no pending sync */
+ rel->no_pending_sync = true;
+ rel->pending_sync = NULL;
+
RelationInitLockInfo(rel); /* see lmgr.c */
RelationInitPhysicalAddr(rel);
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index ab0879138f..fab5052868 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -163,6 +163,7 @@ extern void simple_heap_delete(Relation relation, ItemPointer tid);
extern void simple_heap_update(Relation relation, ItemPointer otid,
HeapTuple tup);
+extern void heap_register_sync(Relation relation);
extern void heap_sync(Relation relation);
extern void heap_update_snapshot(HeapScanDesc scan, Snapshot snapshot);
diff --git a/src/include/catalog/storage.h b/src/include/catalog/storage.h
index 9f638be924..95d7898e25 100644
--- a/src/include/catalog/storage.h
+++ b/src/include/catalog/storage.h
@@ -22,13 +22,16 @@ extern void RelationCreateStorage(RelFileNode rnode, char relpersistence);
extern void RelationDropStorage(Relation rel);
extern void RelationPreserveStorage(RelFileNode rnode, bool atCommit);
extern void RelationTruncate(Relation rel, BlockNumber nblocks);
-
+extern void RelationRemovePendingSync(Relation rel);
/*
* These functions used to be in storage/smgr/smgr.c, which explains the
* naming
*/
extern void smgrDoPendingDeletes(bool isCommit);
extern int smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr);
+extern void smgrDoPendingSyncs(bool isCommit);
+extern void RecordPendingSync(Relation rel);
+bool BufferNeedsWAL(Relation rel, Buffer buf);
extern void AtSubCommit_smgr(void);
extern void AtSubAbort_smgr(void);
extern void PostPrepare_smgr(void);
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index c5826f691d..8a9ea041dd 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -189,6 +189,8 @@ extern BlockNumber RelationGetNumberOfBlocksInFork(Relation relation,
ForkNumber forkNum);
extern void FlushOneBuffer(Buffer buffer);
extern void FlushRelationBuffers(Relation rel);
+extern void FlushRelationBuffersWithoutRelCache(RelFileNode rnode,
+ bool islocal);
extern void FlushDatabaseBuffers(Oid dbid);
extern void DropRelFileNodeBuffers(RelFileNodeBackend rnode,
ForkNumber forkNum, BlockNumber firstDelBlock);
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 1d05465303..0f39f209d3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -185,6 +185,14 @@ typedef struct RelationData
/* use "struct" here to avoid needing to include pgstat.h: */
struct PgStat_TableStatus *pgstat_info; /* statistics collection area */
+
+ /*
+ * no_pending_sync is true if this relation is known not to have pending
+ * syncs. Elsewise searching for registered sync is required if
+ * pending_sync is NULL.
+ */
+ bool no_pending_sync;
+ struct PendingRelSync *pending_sync;
} RelationData;
--
2.16.3
----Next_Part(Mon_Mar_04_12_24_48_2019_788)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="v7-0004-Fix-WAL-skipping-feature.patch"
view thread (27+ messages) latest in thread
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: [email protected]
Cc: [email protected]
Subject: Re: [PATCH 3/4] Add infrastructure to WAL-logging skip feature
In-Reply-To: <no-message-id-1883580@localhost>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox