diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c index b316320833..ee6244f9bc 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -888,8 +888,6 @@ ExtendBufferedRelTo(ExtendBufferedWhat eb, Assert((eb.rel != NULL) != (eb.smgr != NULL)); Assert(eb.smgr == NULL || eb.relpersistence != 0); Assert(extend_to != InvalidBlockNumber && extend_to > 0); - Assert(mode == RBM_NORMAL || mode == RBM_ZERO_ON_ERROR || - mode == RBM_ZERO_AND_LOCK); if (eb.smgr == NULL) { @@ -933,7 +931,13 @@ ExtendBufferedRelTo(ExtendBufferedWhat eb, */ current_size = smgrnblocks(eb.smgr, fork); - if (mode == RBM_ZERO_AND_LOCK) + /* + * Since no-one else can be looking at the page contents yet, there is no + * difference between an exclusive lock and a cleanup-strength lock. Note + * that we pass the original mode to ReadBuffer_common() below, when + * falling back to reading the buffer to a concurrent relation extension. + */ + if (mode == RBM_ZERO_AND_LOCK || mode == RBM_ZERO_AND_CLEANUP_LOCK) flags |= EB_LOCK_TARGET; while (current_size < extend_to) @@ -1008,11 +1012,12 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, { uint32 flags = EB_SKIP_EXTENSION_LOCK; - Assert(mode == RBM_NORMAL || - mode == RBM_ZERO_AND_LOCK || - mode == RBM_ZERO_ON_ERROR); - - if (mode == RBM_ZERO_AND_LOCK) + /* + * Since no-one else can be looking at the page contents yet, there is + * no difference between an exclusive lock and a cleanup-strength + * lock. + */ + if (mode == RBM_ZERO_AND_LOCK || mode == RBM_ZERO_AND_CLEANUP_LOCK) flags |= EB_LOCK_FIRST; return ExtendBufferedRel(EB_SMGR(smgr, relpersistence), @@ -1145,9 +1150,10 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, } /* - * In RBM_ZERO_AND_LOCK mode, grab the buffer content lock before marking - * the page as valid, to make sure that no other backend sees the zeroed - * page before the caller has had a chance to initialize it. + * In RBM_ZERO_AND_LOCK / RBM_ZERO_AND_CLEANUP_LOCK mode, grab the buffer + * content lock before marking the page as valid, to make sure that no + * other backend sees the zeroed page before the caller has had a chance + * to initialize it. * * Since no-one else can be looking at the page contents yet, there is no * difference between an exclusive lock and a cleanup-strength lock. (Note diff --git a/src/test/recovery/meson.build b/src/test/recovery/meson.build index e834ad5e0d..2008958010 100644 --- a/src/test/recovery/meson.build +++ b/src/test/recovery/meson.build @@ -41,6 +41,7 @@ tests += { 't/033_replay_tsp_drops.pl', 't/034_create_database.pl', 't/035_standby_logical_decoding.pl', + 't/036_truncated_dropped.pl', ], }, } diff --git a/src/test/recovery/t/036_truncated_dropped.pl b/src/test/recovery/t/036_truncated_dropped.pl new file mode 100644 index 0000000000..2d5339d9d8 --- /dev/null +++ b/src/test/recovery/t/036_truncated_dropped.pl @@ -0,0 +1,136 @@ +# Copyright (c) 2021-2023, PostgreSQL Global Development Group + +# Tests recovery scenarios where the files are shorter than in the common +# cases, e.g. due to replaying WAL records of a relation that was subsequently +# truncated or dropped. + +use strict; +use warnings; +use PostgreSQL::Test::Cluster; +use Test::More; + +my $node = PostgreSQL::Test::Cluster->new('n1'); + +$node->init(); + +# Disable autovacuum to guarantee VACUUM can remove rows / truncate relations +$node->append_conf( + 'postgresql.conf', qq[ +wal_level = 'replica' +autovacuum = off +]); + +$node->start(); + + +# Test: Replay replay of PRUNE records for a pre-existing, then dropped, +# relation + +$node->safe_psql( + 'postgres', qq[ +CREATE TABLE truncme(i int) WITH (fillfactor = 50); +INSERT INTO truncme SELECT generate_series(1, 1000); +UPDATE truncme SET i = 1; +CHECKPOINT; -- ensure relation exists at start of recovery +VACUUM truncme; -- generate prune records +DROP TABLE truncme; +]); + +$node->stop('immediate'); + +ok($node->start(), + 'replay of PRUNE records for a pre-existing, then dropped, relation'); + + +# Test: Replay of PRUNE records for a newly created, then dropped, relation + +$node->safe_psql( + 'postgres', qq[ +CREATE TABLE truncme(i int) WITH (fillfactor = 50); +INSERT INTO truncme SELECT generate_series(1, 1000); +UPDATE truncme SET i = 1; +VACUUM truncme; -- generate prune records +DROP TABLE truncme; +]); + +$node->stop('immediate'); + +ok($node->start(), + 'replay of PRUNE records for a newly created, then dropped, relation'); + + +# Test: Replay of PRUNE records affecting truncated block. With FPIs used for +# PRUNE. + +$node->safe_psql( + 'postgres', qq[ +CREATE TABLE truncme(i int) WITH (fillfactor = 50); +INSERT INTO truncme SELECT generate_series(1, 1000); +UPDATE truncme SET i = 1; +CHECKPOINT; -- generate FPIs +VACUUM truncme; -- generate prune records +TRUNCATE truncme; -- make blocks non-existing +INSERT INTO truncme SELECT generate_series(1, 10); +]); + +$node->stop('immediate'); + +ok($node->start(), + 'replay of PRUNE records affecting truncated block (FPIs)'); + +is($node->safe_psql('postgres', 'select count(*), sum(i) FROM truncme'), + '10|55', 'table contents as expected after recovery'); +$node->safe_psql('postgres', 'DROP TABLE truncme'); + + +# Test replay of PRUNE records for blocks that are later truncated. Without +# FPIs used for PRUNE. + +$node->safe_psql( + 'postgres', qq[ +CREATE TABLE truncme(i int) WITH (fillfactor = 50); +INSERT INTO truncme SELECT generate_series(1, 1000); +UPDATE truncme SET i = 1; +VACUUM truncme; -- generate prune records +TRUNCATE truncme; -- make blocks non-existing +INSERT INTO truncme SELECT generate_series(1, 10); +]); + +$node->stop('immediate'); + +ok($node->start(), + 'replay of PRUNE records affecting truncated block (no FPIs)'); + +is($node->safe_psql('postgres', 'select count(*), sum(i) FROM truncme'), + '10|55', 'table contents as expected after recovery'); +$node->safe_psql('postgres', 'DROP TABLE truncme'); + + +# Test: Replay of partial truncation via VACUUM + +$node->safe_psql( + 'postgres', qq[ +CREATE TABLE truncme(i int) WITH (fillfactor = 50); +INSERT INTO truncme SELECT generate_series(1, 1000); +UPDATE truncme SET i = i + 1; +-- ensure a mix of pre/post truncation rows +DELETE FROM truncme WHERE i > 500; + +VACUUM truncme; -- should truncate relation + +-- rows at TIDs that previously existed +INSERT INTO truncme SELECT generate_series(1000, 1010); +]); + +$node->stop('immediate'); + +ok($node->start(), 'replay of partial truncation via VACUUM'); + +is( $node->safe_psql( + 'postgres', 'select count(*), sum(i), min(i), max(i) FROM truncme'), + '510|136304|2|1010', + 'table contents as expected after recovery'); +$node->safe_psql('postgres', 'DROP TABLE truncme'); + + +done_testing();