From be03591a4c69224de5b96335aa4a29b3462e2bc9 Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Sun, 10 Mar 2024 22:18:59 +0200 Subject: [PATCH 1/1] Don't destroy SMgrRelations at relcache invalidation With commit 21d9c3ee4e, SMgrRelations remain valid until end of transaction (or longer if they're "pinned"). Relcache invalidation can happen in the middle of a transaction, so we must not destroy them at relcache invalidation anymore. This was revealed by failures in the 'constraints' test in buildfarm animals using -DCLOBBER_CACHE_ALWAYS. That started failing with commit 8af2565248, which was the first commit that started to rely on an SMgrRelation living until end of transaction. Diagnosed-by: Tomas Vondra, Thomas Munro Discussion: https://www.postgresql.org/message-id/CA%2BhUKGK%2B5DOmLaBp3Z7C4S-Yv6yoROvr1UncjH2S1ZbPT8D%2BZg%40mail.gmail.com --- src/backend/utils/cache/relcache.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c index 7ad6a35a50e..2cd19d603fb 100644 --- a/src/backend/utils/cache/relcache.c +++ b/src/backend/utils/cache/relcache.c @@ -2985,9 +2985,6 @@ RelationCacheInvalidate(bool debug_discard) { relation = idhentry->reldesc; - /* Must close all smgr references to avoid leaving dangling ptrs */ - RelationCloseSmgr(relation); - /* * Ignore new relations; no other backend will manipulate them before * we commit. Likewise, before replacing a relation's relfilelocator, @@ -3039,11 +3036,10 @@ RelationCacheInvalidate(bool debug_discard) } /* - * Now zap any remaining smgr cache entries. This must happen before we - * start to rebuild entries, since that may involve catalog fetches which - * will re-open catalog files. + * We cannot destroy the SMgrRelations as there might still be references + * to them, but close the underlying file descriptors. */ - smgrdestroyall(); + smgrreleaseall(); /* Phase 2: rebuild the items found to need rebuild in phase 1 */ foreach(l, rebuildFirstList) -- 2.39.2