From 761ceb93ac3c339c02e2337c43ddd8edbf79d692 Mon Sep 17 00:00:00 2001 From: Matthias van de Meent Date: Fri, 19 Dec 2025 22:12:39 +0100 Subject: [PATCH v1] pg_visibility: Use visibilitymap_count instead of loop This improves performance by a good margin by vectorizing the counting operations. --- contrib/pg_visibility/pg_visibility.c | 31 +++++---------------------- 1 file changed, 5 insertions(+), 26 deletions(-) diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c index 7046c1b5f8e..715f5cdd17c 100644 --- a/contrib/pg_visibility/pg_visibility.c +++ b/contrib/pg_visibility/pg_visibility.c @@ -270,11 +270,8 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS) { Oid relid = PG_GETARG_OID(0); Relation rel; - BlockNumber nblocks; - BlockNumber blkno; - Buffer vmbuffer = InvalidBuffer; - int64 all_visible = 0; - int64 all_frozen = 0; + BlockNumber all_visible = 0; + BlockNumber all_frozen = 0; TupleDesc tupdesc; Datum values[2]; bool nulls[2] = {0}; @@ -284,33 +281,15 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS) /* Only some relkinds have a visibility map */ check_relation_relkind(rel); - nblocks = RelationGetNumberOfBlocks(rel); - - for (blkno = 0; blkno < nblocks; ++blkno) - { - int32 mapbits; - - /* Make sure we are interruptible. */ - CHECK_FOR_INTERRUPTS(); - - /* Get map info. */ - mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer); - if ((mapbits & VISIBILITYMAP_ALL_VISIBLE) != 0) - ++all_visible; - if ((mapbits & VISIBILITYMAP_ALL_FROZEN) != 0) - ++all_frozen; - } + visibilitymap_count(rel, &all_visible, &all_frozen); - /* Clean up. */ - if (vmbuffer != InvalidBuffer) - ReleaseBuffer(vmbuffer); relation_close(rel, AccessShareLock); if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) elog(ERROR, "return type must be a row type"); - values[0] = Int64GetDatum(all_visible); - values[1] = Int64GetDatum(all_frozen); + values[0] = Int64GetDatum((int64) all_visible); + values[1] = Int64GetDatum((int64) all_frozen); PG_RETURN_DATUM(HeapTupleGetDatum(heap_form_tuple(tupdesc, values, nulls))); } -- 2.50.1 (Apple Git-155)