postgrespro.git / summary / log / commit / refs
commit e629a01f6973688f77ecff964d9d6bea9bc4b374
Author: Noah Misch <noah@leadboat.com>
Date: Sat Mar 21 16:38:26 2020 +0000
During heap rebuild, lock any TOAST index until end of transaction.
swap_relation_files() calls toast_get_valid_index() to find and lock
this index, just before swapping with the rebuilt TOAST index. The
latter function releases the lock before returning. Potential for
mischief is low; a concurrent session can issue ALTER INDEX ... SET
(fillfactor = ...), which is not alarming. Nonetheless, changing
pg_class.relfilenode without a lock is unconventional. Back-patch to
9.5 (all supported versions), because another fix needs this.
Discussion: https://postgr.es/m/20191226001521.GA1772687@rfd.leadboat.com
src/backend/access/common/toast_internals.c | 4 ++--
src/backend/commands/cluster.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/src/backend/access/common/toast_internals.c b/src/backend/access/common/toast_internals.c
index 65801a2a84..25a81e5ec6 100644
--- a/src/backend/access/common/toast_internals.c
+++ b/src/backend/access/common/toast_internals.c
@@ -528,8 +528,8 @@ toast_get_valid_index(Oid toastoid, LOCKMODE lock)
validIndexOid = RelationGetRelid(toastidxs[validIndex]);
/* Close the toast relation and all its indexes */
- toast_close_indexes(toastidxs, num_indexes, lock);
- table_close(toastrel, lock);
+ toast_close_indexes(toastidxs, num_indexes, NoLock);
+ table_close(toastrel, NoLock);
return validIndexOid;
}
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 11ce1bb404..fc1cea0236 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -1489,7 +1489,7 @@ finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap,
/* Get the associated valid index to be renamed */
toastidx = toast_get_valid_index(newrel->rd_rel->reltoastrelid,
- AccessShareLock);
+ NoLock);
/* rename the toast table ... */
snprintf(NewToastName, NAMEDATALEN, "pg_toast_%u",
[parent: d60ef94d7639]