From 7f09ba15f287199c4e72f9fb51373664d93304a9 Mon Sep 17 00:00:00 2001 From: Kevin Rocker Date: Wed, 12 Aug 2026 15:58:04 +0200 Subject: [PATCH v6 1/2] Move interrupt checks out of locked regions vacuum_delay_point() and CHECK_FOR_INTERRUPTS() cannot process pending interrupts while interrupts are held. A vacuum delay point may additionally sleep while retaining a buffer content lock. Several call sites make these calls while a lock is held. Move the ANALYZE delay point before scan_analyze_next_block(). Move the first GIN pending-list cleanup delay point before its locks are acquired; an existing delay point already covers transitions between pages. Move the hash bucket cleanup delay point from hashbucketcleanup() up to hashbulkdelete()'s per-bucket loop, before the bucket's cleanup lock is acquired. hashbucketcleanup() is called assuming a lock exists for it's duration, so no part of it is a valid call site. Its other callers, the split-cleanup paths called from insertion, lose the call entirely. A backend running INSERT doesn't do vaccuum cost accounting and there's an active lock, so the call couldn't sleep there anyway. dshash sequential iteration returns each stats entry with its partition lock held and provides no unlocked per-entry boundary, so mark that call with a grep-friendly comment instead. Author: Kevin Rocker Author: Andrey Borodin Reviewed-by: Neil Chen Discussion: https://postgr.es/m/492c6247-43d3-477b-8981-fb0c56767b38%40app.fastmail.com --- src/backend/access/gin/ginfast.c | 5 +++-- src/backend/access/hash/hash.c | 5 +++-- src/backend/commands/analyze.c | 5 ++++- src/backend/utils/activity/pgstat.c | 4 ++++ 4 files changed, 14 insertions(+), 5 deletions(-) diff --git a/src/backend/access/gin/ginfast.c b/src/backend/access/gin/ginfast.c index 46fc60115a8..bb678300b1b 100644 --- a/src/backend/access/gin/ginfast.c +++ b/src/backend/access/gin/ginfast.c @@ -797,6 +797,9 @@ ginInsertCleanup(GinState *ginstate, bool must_empty_list, bool fsm_vac = false; int workMemory; + /* Delay or accept interrupts before acquiring the pending-list locks. */ + vacuum_delay_point(false); + /* * We would like to prevent concurrent cleanup process. For that we will * lock metapage in exclusive mode using LockPage() call. Nobody other @@ -895,8 +898,6 @@ ginInsertCleanup(GinState *ginstate, bool must_empty_list, */ processPendingPage(&accum, &datums, page, FirstOffsetNumber); - vacuum_delay_point(false); - /* * Is it time to flush memory to disk? Flush if we are at the end of * the pending list, or if we have a full row and memory is getting diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c index b2e34d2d45e..3d48355eb08 100644 --- a/src/backend/access/hash/hash.c +++ b/src/backend/access/hash/hash.c @@ -562,6 +562,9 @@ bucket_loop: Page page; bool split_cleanup = false; + /* Delay or accept interrupts before locking the next bucket. */ + vacuum_delay_point(false); + /* Get address of bucket's start page */ bucket_blkno = BUCKET_TO_BLKNO(cachedmetap, cur_bucket); @@ -799,8 +802,6 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, bool retain_pin = false; bool clear_dead_marking = false; - vacuum_delay_point(false); - page = BufferGetPage(buf); opaque = HashPageGetOpaque(page); diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c index 15beb8150de..f171527b5a4 100644 --- a/src/backend/commands/analyze.c +++ b/src/backend/commands/analyze.c @@ -1309,10 +1309,13 @@ acquire_sample_rows(Relation onerel, int elevel, 0); /* Outer loop over blocks to sample */ - while (table_scan_analyze_next_block(scan, stream)) + for (;;) { vacuum_delay_point(true); + if (!table_scan_analyze_next_block(scan, stream)) + break; + while (table_scan_analyze_next_tuple(scan, &liverows, &deadrows, slot)) { /* diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index 4615f610106..51bb78c90be 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -1745,6 +1745,10 @@ pgstat_write_statsfile(void) PgStatShared_Common *shstats; const PgStat_KindInfo *kind_info = NULL; + /* + * CHECK_FOR_INTERRUPTS_WITH_INTERRUPTS_HELD: dshash_seq_next() + * returns with the current hash partition lock still held. + */ CHECK_FOR_INTERRUPTS(); /* -- 2.54.0