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[PATCH 6/7] Fix a few problems in index build progress reporting. 142+ messages / 5 participants [nested] [flat]
* [PATCH 6/7] Fix a few problems in index build progress reporting. @ 2026-03-16 12:53 Antonin Houska <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: Antonin Houska @ 2026-03-16 12:53 UTC (permalink / raw) First, index_build() should not update the progress when being driven by REPACK, because the progress reporting infractructure cannot handle status of two commands at the same time. So far, REPACK with the CONCURRENTLY option neglected this problem altogether, but even the existing REPACK wasn't consistent enough: even if the 'progress' variable in repack_index() was false, it didn't pass the value to index_build(). Second, REPACK (CONCURRENTLY) should not set PROGRESS_REPACK_PHASE to PROGRESS_REPACK_PHASE_FINAL_CLEANUP in rebuild_relation() because it calls finish_heap_swap() anyway (via rebuild_relation_finish_concurrent()), which does the same thing. --- src/backend/bootstrap/bootstrap.c | 2 +- src/backend/catalog/heap.c | 3 ++- src/backend/catalog/index.c | 22 ++++++++++++++++++---- src/backend/catalog/toasting.c | 3 ++- src/backend/commands/cluster.c | 7 ++++--- src/backend/commands/indexcmds.c | 1 + src/include/catalog/index.h | 4 +++- 7 files changed, 31 insertions(+), 11 deletions(-) diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c index 68a42de0889..1c8226c6d67 100644 --- a/src/backend/bootstrap/bootstrap.c +++ b/src/backend/bootstrap/bootstrap.c @@ -1181,7 +1181,7 @@ build_indices(void) heap = table_open(ILHead->il_heap, NoLock); ind = index_open(ILHead->il_ind, NoLock); - index_build(heap, ind, ILHead->il_info, false, false); + index_build(heap, ind, ILHead->il_info, false, false, false); index_close(ind, NoLock); table_close(heap, NoLock); diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index 5748aa9a1a9..ae6b7cda3dd 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -3570,7 +3570,8 @@ RelationTruncateIndexes(Relation heapRelation) /* Initialize the index and rebuild */ /* Note: we do not need to re-establish pkey setting */ - index_build(heapRelation, currentIndex, indexInfo, true, false); + index_build(heapRelation, currentIndex, indexInfo, true, false, + true); /* We're done with this index */ index_close(currentIndex, NoLock); diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c index 544dd0d6e3d..13284f1d708 100644 --- a/src/backend/catalog/index.c +++ b/src/backend/catalog/index.c @@ -715,6 +715,9 @@ UpdateIndexRelation(Oid indexoid, * already exists. * INDEX_CREATE_PARTITIONED: * create a partitioned index (table must be partitioned) + * INDEX_CREATE_REPORT_PROGRESS: + * update the backend's progress information during index build. + * constr_flags: flags passed to index_constraint_create * (only if INDEX_CREATE_ADD_CONSTRAINT is set) * allow_system_table_mods: allow table to be a system catalog @@ -760,6 +763,7 @@ index_create(Relation heapRelation, bool invalid = (flags & INDEX_CREATE_INVALID) != 0; bool concurrent = (flags & INDEX_CREATE_CONCURRENT) != 0; bool partitioned = (flags & INDEX_CREATE_PARTITIONED) != 0; + bool progress = (flags & INDEX_CREATE_REPORT_PROGRESS) != 0; char relkind; TransactionId relfrozenxid; MultiXactId relminmxid; @@ -1276,7 +1280,8 @@ index_create(Relation heapRelation, } else { - index_build(heapRelation, indexRelation, indexInfo, false, true); + index_build(heapRelation, indexRelation, indexInfo, false, true, + progress); } /* @@ -1455,6 +1460,12 @@ index_create_copy(Relation heapRelation, Oid oldIndexId, Oid tablespaceOid, stattargets[i].isnull = isnull; } + /* + * Note: The current callers do not need INDEX_CREATE_REPORT_PROGRESS. If + * 'concurrently' is true, there is no build at all. Otherwise the index + * build is a sub-command of REPACK. The current infrastructure does not + * allow two commands to report their progress at the same time. + */ if (concurrently) flags = INDEX_CREATE_SKIP_BUILD | INDEX_CREATE_CONCURRENT; @@ -1545,7 +1556,7 @@ index_concurrently_build(Oid heapRelationId, indexInfo->ii_BrokenHotChain = false; /* Now build the index */ - index_build(heapRel, indexRelation, indexInfo, false, true); + index_build(heapRel, indexRelation, indexInfo, false, true, true); /* Roll back any GUC changes executed by index functions */ AtEOXact_GUC(false, save_nestlevel); @@ -3018,6 +3029,7 @@ index_update_stats(Relation rel, * * isreindex indicates we are recreating a previously-existing index. * parallel indicates if parallelism may be useful. + * progress indicates if the backend should update its progress info. * * Note: before Postgres 8.2, the passed-in heap and index Relations * were automatically closed by this routine. This is no longer the case. @@ -3028,7 +3040,8 @@ index_build(Relation heapRelation, Relation indexRelation, IndexInfo *indexInfo, bool isreindex, - bool parallel) + bool parallel, + bool progress) { IndexBuildResult *stats; Oid save_userid; @@ -3079,6 +3092,7 @@ index_build(Relation heapRelation, RestrictSearchPath(); /* Set up initial progress report status */ + if (progress) { const int progress_index[] = { PROGRESS_CREATEIDX_PHASE, @@ -3836,7 +3850,7 @@ reindex_index(const ReindexStmt *stmt, Oid indexId, /* Initialize the index and rebuild */ /* Note: we do not need to re-establish pkey setting */ - index_build(heapRelation, iRel, indexInfo, true, true); + index_build(heapRelation, iRel, indexInfo, true, true, progress); /* Re-allow use of target index */ ResetReindexProcessing(); diff --git a/src/backend/catalog/toasting.c b/src/backend/catalog/toasting.c index 078a1cf5127..73c41360ae9 100644 --- a/src/backend/catalog/toasting.c +++ b/src/backend/catalog/toasting.c @@ -331,7 +331,8 @@ create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid, BTREE_AM_OID, rel->rd_rel->reltablespace, collationIds, opclassIds, NULL, coloptions, NULL, (Datum) 0, - INDEX_CREATE_IS_PRIMARY, 0, true, true, NULL); + INDEX_CREATE_IS_PRIMARY | INDEX_CREATE_REPORT_PROGRESS, 0, + true, true, NULL); table_close(toast_rel, NoLock); diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index d89be1b9533..4fd10a5e7b3 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -1164,9 +1164,6 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, rebuild_relation_finish_concurrent(NewHeap, OldHeap, ident_idx, frozenXid, cutoffMulti); - - pgstat_progress_update_param(PROGRESS_REPACK_PHASE, - PROGRESS_REPACK_PHASE_FINAL_CLEANUP); } else { @@ -3694,6 +3691,10 @@ rebuild_relation_finish_concurrent(Relation NewHeap, Relation OldHeap, relpersistence = OldHeap->rd_rel->relpersistence; is_system_catalog = IsSystemRelation(OldHeap); + /* + * finish_heap_swap() sets the phase too, but here we need some swapping + * in advance. + */ pgstat_progress_update_param(PROGRESS_REPACK_PHASE, PROGRESS_REPACK_PHASE_SWAP_REL_FILES); diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 4b37d92a49e..8d1e8a20998 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -1231,6 +1231,7 @@ DefineIndex(ParseState *pstate, flags |= INDEX_CREATE_PARTITIONED; if (stmt->primary) flags |= INDEX_CREATE_IS_PRIMARY; + flags |= INDEX_CREATE_REPORT_PROGRESS; /* * If the table is partitioned, and recursion was declined but partitions diff --git a/src/include/catalog/index.h b/src/include/catalog/index.h index 144e241ebd3..6c7f0fee115 100644 --- a/src/include/catalog/index.h +++ b/src/include/catalog/index.h @@ -71,6 +71,7 @@ extern void index_check_primary_key(Relation heapRel, #define INDEX_CREATE_IF_NOT_EXISTS (1 << 4) #define INDEX_CREATE_PARTITIONED (1 << 5) #define INDEX_CREATE_INVALID (1 << 6) +#define INDEX_CREATE_REPORT_PROGRESS (1 << 7) extern Oid index_create(Relation heapRelation, const char *indexRelationName, @@ -152,7 +153,8 @@ extern void index_build(Relation heapRelation, Relation indexRelation, IndexInfo *indexInfo, bool isreindex, - bool parallel); + bool parallel, + bool progress); extern void validate_index(Oid heapId, Oid indexId, Snapshot snapshot); -- 2.47.3 --=-=-= Content-Type: text/x-diff Content-Disposition: attachment; filename=v42-0007-Teach-snapshot-builder-to-skip-transactions-running-.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). @ 2026-06-16 06:49 ChangAo Chen <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw) When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index faa07d1a118..2879c8af574 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.47.3 --op6mnexl7cn72cto Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename=v2-0002-fixups.patch ^ permalink raw reply [nested|flat] 142+ messages in thread
* Do not lock tables in get_tables_to_repack @ 2026-06-16 07:34 =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> 0 siblings, 2 replies; 142+ messages in thread From: =?utf-8?B?Y2NhNTUwNw==?= @ 2026-06-16 07:34 UTC (permalink / raw) To: =?utf-8?B?cGdzcWwtaGFja2Vycw==?= <[email protected]> Hi hackers, When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). Thoughts? -- Regards, ChangAo Chen Attachments: [application/octet-stream] v1-0001-Do-not-lock-tables-in-get_tables_to_repack.patch (5.4K, ../../[email protected]/2-v1-0001-Do-not-lock-tables-in-get_tables_to_repack.patch) download | inline diff: From fa5c3073f2f41cf3c8ab7c9663b681e6140a4824 Mon Sep 17 00:00:00 2001 From: ChangAo Chen <[email protected]> Date: Tue, 16 Jun 2026 14:49:49 +0800 Subject: [PATCH v1] Do not lock tables in get_tables_to_repack(). When doing a whole database repack, we build a list of repackable tables and take a lock on them to prevent concurrent drops. But concurrent drops can always happen after we build the list because we process each table in a separate transaction. The ConditionalLockRelationOid() also makes the default behavior like SKIP_LOCKED, which is unexpected. To remove the locks, we need to make repack_is_permitted_for_relation() handles concurrent drops correctly: it should not report an error when failing to search the syscache in pg_class_aclcheck(). Use pg_class_aclcheck_ext() instead to detect a concurrent drop. Also check the return value of get_rel_name(). While at it, replace relation_close() with table_close() to match the table_open(). --- src/backend/commands/repack.c | 67 ++++++++++------------------------- 1 file changed, 19 insertions(+), 48 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index ec100e3eef5..6f25effeed2 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -2159,22 +2159,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) index = (Form_pg_index) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the index's table, to ensure it - * doesn't go away while we collect the list. If we cannot, just - * disregard it. Be sure to release this if we ultimately decide - * not to process the table! - */ - if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock)) - continue; - - /* Verify that the table still exists; skip if not */ classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); if (!HeapTupleIsValid(classtup)) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } classForm = (Form_pg_class) GETSTRUCT(classtup); /* Skip temp relations belonging to other sessions */ @@ -2182,7 +2169,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) !isTempOrTempToastNamespace(classForm->relnamespace)) { ReleaseSysCache(classtup); - UnlockRelationOid(index->indrelid, AccessShareLock); continue; } @@ -2191,10 +2177,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, GetUserId())) - { - UnlockRelationOid(index->indrelid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2218,45 +2201,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) class = (Form_pg_class) GETSTRUCT(tuple); - /* - * Try to obtain a light lock on the table, to ensure it doesn't - * go away while we collect the list. If we cannot, just - * disregard the table. Be sure to release this if we ultimately - * decide not to process the table! - */ - if (!ConditionalLockRelationOid(class->oid, AccessShareLock)) - continue; - - /* Verify that the table still exists */ - if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid))) - { - UnlockRelationOid(class->oid, AccessShareLock); - continue; - } - /* Can only process plain tables and matviews */ if (class->relkind != RELKIND_RELATION && class->relkind != RELKIND_MATVIEW) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Skip temp relations belonging to other sessions */ if (class->relpersistence == RELPERSISTENCE_TEMP && !isTempOrTempToastNamespace(class->relnamespace)) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, GetUserId())) - { - UnlockRelationOid(class->oid, AccessShareLock); continue; - } /* Use a permanent memory context for the result list */ oldcxt = MemoryContextSwitchTo(permcxt); @@ -2269,7 +2227,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) } table_endscan(scan); - relation_close(catalog, AccessShareLock); + table_close(catalog, AccessShareLock); return rtcs; } @@ -2347,15 +2305,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) { + bool is_missing = false; + Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK) + if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK) return true; - ereport(WARNING, - errmsg("permission denied to execute %s on \"%s\", skipping it", - RepackCommandAsString(cmd), - get_rel_name(relid))); + /* Report a warning if the relation still exists. */ + if (!is_missing) + { + char *relname; + + relname = get_rel_name(relid); + if (relname != NULL) + { + ereport(WARNING, + errmsg("permission denied to execute %s on \"%s\", skipping it", + RepackCommandAsString(cmd), relname)); + + pfree(relname); + } + } return false; } -- 2.34.1 ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-06-27 19:56 Bharath Rupireddy <[email protected]> parent: =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> 1 sibling, 0 replies; 142+ messages in thread From: Bharath Rupireddy @ 2026-06-27 19:56 UTC (permalink / raw) To: cca5507 <[email protected]>; +Cc: pgsql-hackers <[email protected]>; Antonin Houska <[email protected]>; Alvaro Herrera <[email protected]> Hi, On Tue, Jun 16, 2026 at 12:35 AM cca5507 <[email protected]> wrote: > > Hi hackers, > > When doing a whole database repack, we build a list of repackable > tables and take a lock on them to prevent concurrent drops. But > concurrent drops can always happen after we build the list because > we process each table in a separate transaction. The > ConditionalLockRelationOid() also makes the default behavior like > SKIP_LOCKED, which is unexpected. > > To remove the locks, we need to make repack_is_permitted_for_relation() > handles concurrent drops correctly: it should not report an error > when failing to search the syscache in pg_class_aclcheck(). Use > pg_class_aclcheck_ext() instead to detect a concurrent drop. Also > check the return value of get_rel_name(). > > Thoughts? I don't have a strong opinion on fixing this for REPACK. For vacuum, we wanted to get consistent behavior across all modes of invoking it [1]. Whether to handle concurrent drops for REPACK depends on how long it spends scanning pg_index/pg_class in get_tables_to_repack. Also, vacuum is more commonly run database-wide (against all tables), and without field experience showing this is a real problem for REPACK, I'm not sure the fix is needed. That said, others may have a different take - adding the REPACK authors here for their input. [1] https://www.postgresql.org/message-id/CALj2ACUbhDFJWSwiyoUxXED2S2fr9Xis%3D08Rnjq53UzBE4FvzA%40mail.g... -- Bharath Rupireddy Amazon Web Services: https://aws.amazon.com ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-07-07 16:53 Álvaro Herrera <[email protected]> parent: =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> 1 sibling, 1 reply; 142+ messages in thread From: Álvaro Herrera @ 2026-07-07 16:53 UTC (permalink / raw) To: cca5507 <[email protected]>; +Cc: pgsql-hackers <[email protected]> On 2026-Jun-16, cca5507 wrote: > Hi hackers, > > When doing a whole database repack, we build a list of repackable > tables and take a lock on them to prevent concurrent drops. But > concurrent drops can always happen after we build the list because > we process each table in a separate transaction. Not only that. We have actually three ways to obtain the list of tables to repack, and only one of these obtains the locks. So this code is internally inconsistent. I agree that we should do something like your patch. I wanted to be a little more defensive though; how about the attached? -- Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/ ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-07-08 02:36 =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> parent: Álvaro Herrera <[email protected]> 0 siblings, 1 reply; 142+ messages in thread From: =?utf-8?B?Y2NhNTUwNw==?= @ 2026-07-08 02:36 UTC (permalink / raw) To: =?utf-8?B?w4FsdmFybyBIZXJyZXJh?= <[email protected]>; +Cc: =?utf-8?B?cGdzcWwtaGFja2Vycw==?= <[email protected]> > > Hi hackers, > > > > When doing a whole database repack, we build a list of repackable > > tables and take a lock on them to prevent concurrent drops. But > > concurrent drops can always happen after we build the list because > > we process each table in a separate transaction. > > Not only that. We have actually three ways to obtain the list of tables > to repack, and only one of these obtains the locks. So this code is > internally inconsistent. I agree that we should do something like your > patch. I wanted to be a little more defensive though; how about the > attached? - classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); + classtup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(index->indrelid)); Do we really need to copy it? We hold a refcount on it so it won't be freed until we release it. Otherwise LGTM. -- Regards, ChangAo Chen ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-07-10 14:22 Álvaro Herrera <[email protected]> parent: =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> 0 siblings, 1 reply; 142+ messages in thread From: Álvaro Herrera @ 2026-07-10 14:22 UTC (permalink / raw) To: cca5507 <[email protected]>; +Cc: pgsql-hackers <[email protected]> On 2026-Jul-08, cca5507 wrote: > - classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); > + classtup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(index->indrelid)); > > Do we really need to copy it? We hold a refcount on it so it won't be freed > until we release it. Otherwise LGTM. Yeah, I guess it doesn't matter. I have removed the copy and updated some comments. I also realized that there are some places where we weren't dealing correctly with the possibility that the relation goes away, or is replaced with something different, so I added that too. While looking at it I also realized that get_tables_to_repack_partitioned is likewise not careful enough about it: we do IndexGetRelation(, false) which fails hard if the pg_index tuple cannot be found, which is the wrong thing to do. At the same time, it's annoying that half of the code that clearly belongs in that routine is actually in ExecRepack(). I moved that to where it rightfully belongs. (The only somewhat annoying thing is that we have to NULL-out the Relation pointer after returning; but that's not *too* bad IMO.) Any opinions on this? -- Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/ "No me acuerdo, pero no es cierto. No es cierto, y si fuera cierto, no me acuerdo." (Augusto Pinochet a una corte de justicia) ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-07-10 16:03 Bharath Rupireddy <[email protected]> parent: Álvaro Herrera <[email protected]> 0 siblings, 1 reply; 142+ messages in thread From: Bharath Rupireddy @ 2026-07-10 16:03 UTC (permalink / raw) To: Álvaro Herrera <[email protected]>; +Cc: cca5507 <[email protected]>; pgsql-hackers <[email protected]> Hi, On Fri, Jul 10, 2026 at 7:22 AM Álvaro Herrera <[email protected]> wrote: > > On 2026-Jul-08, cca5507 wrote: > > > - classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid)); > > + classtup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(index->indrelid)); > > > > Do we really need to copy it? We hold a refcount on it so it won't be freed > > until we release it. Otherwise LGTM. Thanks for committing this. Here is my overall take. Even before this commit, a database-wide REPACK does not error on a concurrently dropped table. get_tables_to_repack takes a brief lock on each table before the ACL check, which blocks a concurrent drop while the list is being built. Later each table is re-opened under its lock and skipped if it is already gone. So the brief lock is not needed for correctness. What it does is let an unprivileged user lock relations it may not even be allowed to repack, including system catalogs, before we have checked its privileges. I am fine with removing the lock as the commit did. I would also like to tighten repack_is_permitted_for_relation so a caller that holds a lock still errors out on a missing relation instead of skipping it silently (https://www.postgresql.org/message-id/akPhEffRipH4isWF%40nathan). Attached as a follow-up patch. Please have a look. > Yeah, I guess it doesn't matter. I have removed the copy and updated > some comments. I also realized that there are some places where we > weren't dealing correctly with the possibility that the relation goes > away, or is replaced with something different, so I added that too. I agree that the SearchSysCacheCopy1 in v2-0002 adds no benefit. Since no lock is held on the relation, there is no point in copying the syscache tuple. > While looking at it I also realized that get_tables_to_repack_partitioned > is likewise not careful enough about it: we do IndexGetRelation(, false) > which fails hard if the pg_index tuple cannot be found, which is the > wrong thing to do. > > At the same time, it's annoying that half of the code that clearly > belongs in that routine is actually in ExecRepack(). I moved that to > where it rightfully belongs. (The only somewhat annoying thing is that > we have to NULL-out the Relation pointer after returning; but that's not > *too* bad IMO.) > > Any opinions on this? I will take a closer look at this in a bit. -- Bharath Rupireddy Amazon Web Services: https://aws.amazon.com Attachments: [application/octet-stream] v1-0001-Tighten-ACL-check-in-repack_is_permitted_for_rela.patch (5.1K, ../../CALj2ACX3pyuRS8++6L20cJUMRTf_qbbVp69J1btJ3y6=77e5gw@mail.gmail.com/2-v1-0001-Tighten-ACL-check-in-repack_is_permitted_for_rela.patch) download | inline diff: From 6729b2f14ed623a8b38f5a530b8c85c96bfd5b40 Mon Sep 17 00:00:00 2001 From: Bharath Rupireddy <[email protected]> Date: Fri, 10 Jul 2026 15:42:47 +0000 Subject: [PATCH v1] Tighten ACL check in repack_is_permitted_for_relation() Commit c71d43025d7 made repack_is_permitted_for_relation() use _ext() and skip a concurrently dropped relation silently. That is fine for the callers that hold no lock on the relation, but it is applied unconditionally, including where we may already hold a lock on the relation whose ACL is checked. In that case missing a relation is not fine, so this made the code more brittle: a missing relation there would indicate a bug and should error out rather than be skipped silently. Add a missing_ok flag so the silent skip is done only where no lock is held. Callers that hold a lock pass false and still error out on a missing relation. --- src/backend/commands/repack.c | 38 ++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 12 deletions(-) diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index 02883fe34a4..b09be65da3b 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -172,8 +172,8 @@ static List *get_tables_to_repack(RepackCommand cmd, bool usingindex, static List *get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, bool rel_is_index, MemoryContext permcxt); -static bool repack_is_permitted_for_relation(RepackCommand cmd, - Oid relid, Oid userid); +static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, + Oid userid, bool missing_ok); static void apply_concurrent_changes(BufFile *file, ChangeContext *chgcxt); static void apply_concurrent_insert(Relation rel, TupleTableSlot *slot, @@ -724,7 +724,7 @@ cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Assert(CheckRelationLockedByMe(OldHeap, lmode, false)); /* Check that the user still has privileges for the relation */ - if (!repack_is_permitted_for_relation(cmd, tableOid, userid)) + if (!repack_is_permitted_for_relation(cmd, tableOid, userid, false)) { relation_close(OldHeap, lmode); return false; @@ -2198,7 +2198,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, index->indrelid, - GetUserId())) + GetUserId(), true)) continue; /* Use a permanent memory context for the result list */ @@ -2235,7 +2235,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt) /* noisily skip rels which the user can't process */ if (!repack_is_permitted_for_relation(cmd, class->oid, - GetUserId())) + GetUserId(), true)) continue; /* Use a permanent memory context for the result list */ @@ -2304,7 +2304,7 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, * leaf partition despite having them on the partitioned table. Skip * if so. */ - if (!repack_is_permitted_for_relation(cmd, table_oid, GetUserId())) + if (!repack_is_permitted_for_relation(cmd, table_oid, GetUserId(), true)) continue; /* Use a permanent memory context for the result list */ @@ -2321,16 +2321,21 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid, /* - * Return whether userid has privileges to execute REPACK on relid. + * Check whether the passed-in user has privileges to execute REPACK on the + * relation. * - * Caller may not have a lock on the relation, so it could have been - * dropped concurrently. In that case, silently return false. + * missing_ok should be passed only by callers that hold no lock on the + * relation, where a concurrent drop is possible and fine to skip. A caller + * that holds a lock must not pass it: there a missing relation would indicate + * a bug and should error out rather than be silently skipped. * * If the relation does exist but the user doesn't have the required - * privs, emit a WARNING and return false. Otherwise, return true. + * privileges, emit a WARNING and return false to let the caller + * decide what to do with this relation. */ static bool -repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) +repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid, + bool missing_ok) { bool is_missing = false; AclResult result; @@ -2338,9 +2343,18 @@ repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid) Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK); - result = pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing); + result = pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, + missing_ok ? &is_missing : NULL); + + /* + * If the relation was concurrently dropped, nothing to do. Note that this + * is only reachable when the caller specified missing_ok. + */ if (is_missing) + { + Assert(missing_ok); return false; + } if (result == ACLCHECK_OK) return true; -- 2.47.3 ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-07-10 17:34 Bharath Rupireddy <[email protected]> parent: Bharath Rupireddy <[email protected]> 0 siblings, 1 reply; 142+ messages in thread From: Bharath Rupireddy @ 2026-07-10 17:34 UTC (permalink / raw) To: Álvaro Herrera <[email protected]>; +Cc: cca5507 <[email protected]>; pgsql-hackers <[email protected]> Hi, On Fri, Jul 10, 2026 at 9:03 AM Bharath Rupireddy <[email protected]> wrote: > > > While looking at it I also realized that get_tables_to_repack_partitioned > > is likewise not careful enough about it: we do IndexGetRelation(, false) > > which fails hard if the pg_index tuple cannot be found, which is the > > wrong thing to do. Agreed. For a single-level partitioned table, dropping a leaf blocks on the parent's AccessExclusiveLock, which REPACK holds, so the leaf can't go away mid-build. But for a multi-level table, REPACK holds a lock only on the top parent, so a lower-level leaf whose immediate parent is an intermediate table isn't protected and can be dropped concurrently. So IndexGetRelation(, false) failing hard there is indeed the wrong thing. > > At the same time, it's annoying that half of the code that clearly > > belongs in that routine is actually in ExecRepack(). I moved that to > > where it rightfully belongs. +1, that's a good cleanup. That code clearly belongs in get_tables_to_repack_partitioned(). >> (The only somewhat annoying thing is that > > we have to NULL-out the Relation pointer after returning; but that's not > > *too* bad IMO.) That's fine. We already NULL out rel after get_tables_to_repack_partitioned() today, so the patch isn't adding anything new there. Relying on a non-NULL return from process_single_relation() to mean partitioned table is a little indirect on first read, but the comments explains it well, and I wouldn't complicate the code to avoid it. > > Any opinions on this? > > I will take a closer look at this in a bit. Patch looks good to me. One nit: + table_oid = IndexGetRelation(child_oid, true); + if (!OidIsValid(table_oid)) + continue; How about a short comment on why this is needed even with a lock on the parent, since that lock doesn't cover lower-level leaves in a multi-level partition tree? -- Bharath Rupireddy Amazon Web Services: https://aws.amazon.com ^ permalink raw reply [nested|flat] 142+ messages in thread
* Re: Do not lock tables in get_tables_to_repack @ 2026-07-11 14:50 =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> parent: Bharath Rupireddy <[email protected]> 0 siblings, 0 replies; 142+ messages in thread From: =?utf-8?B?Y2NhNTUwNw==?= @ 2026-07-11 14:50 UTC (permalink / raw) To: =?utf-8?B?QmhhcmF0aCBSdXBpcmVkZHk=?= <[email protected]>; =?utf-8?B?w4FsdmFybyBIZXJyZXJh?= <[email protected]>; +Cc: =?utf-8?B?cGdzcWwtaGFja2Vycw==?= <[email protected]> > > > Any opinions on this? > > > > I will take a closer look at this in a bit. > > Patch looks good to me. One nit: > > + table_oid = IndexGetRelation(child_oid, true); > + if (!OidIsValid(table_oid)) > + continue; > > How about a short comment on why this is needed even with a lock on > the parent, since that lock doesn't cover lower-level leaves in a > multi-level partition tree? I think it's worth a comment, too. Patch LGTM. -- Regards, ChangAo Chen ^ permalink raw reply [nested|flat] 142+ messages in thread
end of thread, other threads:[~2026-07-11 14:50 UTC | newest] Thread overview: 142+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2026-03-16 12:53 [PATCH 6/7] Fix a few problems in index build progress reporting. Antonin Houska <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <[email protected]> 2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> 2026-06-27 19:56 ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <[email protected]> 2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <[email protected]> 2026-07-08 02:36 ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <[email protected]> 2026-07-10 14:22 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <[email protected]> 2026-07-10 16:03 ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <[email protected]> 2026-07-10 17:34 ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <[email protected]> 2026-07-11 14:50 ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <[email protected]>
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