diff options
Diffstat (limited to 'src/backend/access/heap/heapam.c')
| -rw-r--r-- | src/backend/access/heap/heapam.c | 67 |
1 files changed, 23 insertions, 44 deletions
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index b661d9811eb..a9d5b109a5e 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -6447,9 +6447,9 @@ FreezeMultiXactId(MultiXactId multi, uint16 t_infomask, * XIDs or MultiXactIds that will need to be processed by a future VACUUM. * * VACUUM caller must assemble HeapTupleFreeze freeze plan entries for every - * tuple that we returned true for, and call heap_freeze_execute_prepared to - * execute freezing. Caller must initialize pagefrz fields for page as a - * whole before first call here for each heap page. + * tuple that we returned true for, and then execute freezing. Caller must + * initialize pagefrz fields for page as a whole before first call here for + * each heap page. * * VACUUM caller decides on whether or not to freeze the page as a whole. * We'll often prepare freeze plans for a page that caller just discards. @@ -6765,35 +6765,19 @@ heap_execute_freeze_tuple(HeapTupleHeader tuple, HeapTupleFreeze *frz) } /* - * heap_freeze_execute_prepared - * - * Executes freezing of one or more heap tuples on a page on behalf of caller. - * Caller passes an array of tuple plans from heap_prepare_freeze_tuple. - * Caller must set 'offset' in each plan for us. Note that we destructively - * sort caller's tuples array in-place, so caller had better be done with it. - * - * WAL-logs the changes so that VACUUM can advance the rel's relfrozenxid - * later on without any risk of unsafe pg_xact lookups, even following a hard - * crash (or when querying from a standby). We represent freezing by setting - * infomask bits in tuple headers, but this shouldn't be thought of as a hint. - * See section on buffer access rules in src/backend/storage/buffer/README. + * Perform xmin/xmax XID status sanity checks before actually executing freeze + * plans. + * + * heap_prepare_freeze_tuple doesn't perform these checks directly because + * pg_xact lookups are relatively expensive. They shouldn't be repeated by + * successive VACUUMs that each decide against freezing the same page. */ void -heap_freeze_execute_prepared(Relation rel, Buffer buffer, - TransactionId snapshotConflictHorizon, - HeapTupleFreeze *tuples, int ntuples) +heap_pre_freeze_checks(Buffer buffer, + HeapTupleFreeze *tuples, int ntuples) { Page page = BufferGetPage(buffer); - Assert(ntuples > 0); - - /* - * Perform xmin/xmax XID status sanity checks before critical section. - * - * heap_prepare_freeze_tuple doesn't perform these checks directly because - * pg_xact lookups are relatively expensive. They shouldn't be repeated - * by successive VACUUMs that each decide against freezing the same page. - */ for (int i = 0; i < ntuples; i++) { HeapTupleFreeze *frz = tuples + i; @@ -6832,8 +6816,19 @@ heap_freeze_execute_prepared(Relation rel, Buffer buffer, xmax))); } } +} - START_CRIT_SECTION(); +/* + * Helper which executes freezing of one or more heap tuples on a page on + * behalf of caller. Caller passes an array of tuple plans from + * heap_prepare_freeze_tuple. Caller must set 'offset' in each plan for us. + * Must be called in a critical section that also marks the buffer dirty and, + * if needed, emits WAL. + */ +void +heap_freeze_prepared_tuples(Buffer buffer, HeapTupleFreeze *tuples, int ntuples) +{ + Page page = BufferGetPage(buffer); for (int i = 0; i < ntuples; i++) { @@ -6844,22 +6839,6 @@ heap_freeze_execute_prepared(Relation rel, Buffer buffer, htup = (HeapTupleHeader) PageGetItem(page, itemid); heap_execute_freeze_tuple(htup, frz); } - - MarkBufferDirty(buffer); - - /* Now WAL-log freezing if necessary */ - if (RelationNeedsWAL(rel)) - { - log_heap_prune_and_freeze(rel, buffer, snapshotConflictHorizon, - false, /* no cleanup lock required */ - PRUNE_VACUUM_SCAN, - tuples, ntuples, - NULL, 0, /* redirected */ - NULL, 0, /* dead */ - NULL, 0); /* unused */ - } - - END_CRIT_SECTION(); } /* |