From 06689ada5011e1abeadaa0d33538e0b4069e5723 Mon Sep 17 00:00:00 2001 From: Melanie Plageman Date: Thu, 20 Mar 2025 16:09:41 -0400 Subject: [PATCH v10 2/2] test backtrack --- src/backend/access/nbtree/nbtree.c | 4 + src/test/modules/test_misc/meson.build | 1 + .../modules/test_misc/t/008_vacuum_btree.pl | 96 +++++++++++++++++++ 3 files changed, 101 insertions(+) create mode 100644 src/test/modules/test_misc/t/008_vacuum_btree.pl diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c index 353600414a2..be29c4e70e2 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -32,6 +32,7 @@ #include "storage/lmgr.h" #include "utils/fmgrprotos.h" #include "utils/index_selfuncs.h" +#include "utils/injection_point.h" #include "utils/memutils.h" @@ -1178,6 +1179,7 @@ backtrack: attempt_pagedel = false; backtrack_to = P_NONE; + INJECTION_POINT("nbtree-vacuum-page"); _bt_lockbuf(rel, buf, BT_READ); page = BufferGetPage(buf); opaque = NULL; @@ -1468,6 +1470,8 @@ backtrack: /* check for vacuum delay while not holding any buffer lock */ vacuum_delay_point(false); + INJECTION_POINT("nbtree-vacuum-page-backtrack"); + /* * We can't use _bt_getbuf() here because it always applies * _bt_checkpage(), which will barf on an all-zero page. We want to diff --git a/src/test/modules/test_misc/meson.build b/src/test/modules/test_misc/meson.build index 9c50de7efb0..ed0822f19ee 100644 --- a/src/test/modules/test_misc/meson.build +++ b/src/test/modules/test_misc/meson.build @@ -16,6 +16,7 @@ tests += { 't/005_timeouts.pl', 't/006_signal_autovacuum.pl', 't/007_catcache_inval.pl', + 't/008_vacuum_btree.pl', ], }, } diff --git a/src/test/modules/test_misc/t/008_vacuum_btree.pl b/src/test/modules/test_misc/t/008_vacuum_btree.pl new file mode 100644 index 00000000000..d393e1809ce --- /dev/null +++ b/src/test/modules/test_misc/t/008_vacuum_btree.pl @@ -0,0 +1,96 @@ +# Copyright (c) 2024, PostgreSQL Global Development Group + +# Test btree vacuum + +use strict; +use warnings; +use PostgreSQL::Test::Cluster; +use Test::More; + +if ($ENV{enable_injection_points} ne 'yes') +{ + plan skip_all => 'Injection points not supported by this build'; +} + +my $node = PostgreSQL::Test::Cluster->new('node'); +$node->init; + +# Turn autovacuum off for the cluster. This could be done at the table level +# instead. However, since this file exercises vacuum, turn off autovacuum +# globally. This also allows use of non-local injection points in vacuum code. +$node->append_conf('postgresql.conf', 'autovacuum = off'); +$node->start; + +# Check if extension injection_points is available +if (!$node->check_extension('injection_points')) +{ + plan skip_all => 'Extension injection_points not installed'; +} + +$node->safe_psql('postgres', 'CREATE EXTENSION injection_points;'); + +my $psql_session = $node->background_psql('postgres'); + +# Create a table with an index filled with dead index entries +$node->safe_psql('postgres', q[ + create table test_backtrack (col1 int); + insert into test_backtrack select generate_series(1,800); + create index on test_backtrack(col1); + delete from test_backtrack; + ] +); + +# Attach to two injection points. The first one will allow us to stop between +# vacuuming each index page. The second is our validation that we did backtrack. +$psql_session->query_safe( + qq[ + SELECT injection_points_set_local(); + SELECT injection_points_attach('nbtree-vacuum-page', 'wait'); + SELECT injection_points_attach('nbtree-vacuum-page-backtrack', 'wait'); +]); + +# Start a vacuum of the table and index. +$psql_session->query_until( + qr/starting_bg_psql/, + q(\echo starting_bg_psql + vacuum (index_cleanup on, parallel 0) test_backtrack; + )); + +# The index vacuum should be waiting on our first injection point and is yet to +# process any pages. +$node->wait_for_event('client backend', 'nbtree-vacuum-page'); + +# Wake up vacuum so it can process the first index leaf page. +$node->safe_psql('postgres', "SELECT injection_points_wakeup('nbtree-vacuum-page');"); + +# The first index leaf page is now vacuumed and vacuum should be waiting again +# on the first injection point. +$node->wait_for_event('client backend', 'nbtree-vacuum-page'); + +# Insert data while vacuum is waiting to process the next leaf page. The +# inserted data will force a page split in which some tuples from unprocessed +# leaf pages will be moved to the first already vacuumed leaf page. +$node->safe_psql('postgres', + "insert into test_backtrack select generate_series(1,300);"); + +# Now we want the vacuum to continue. We don't want to wait on our first break +# point again. +# We need to make sure we are waiting before detaching and issuing a wakeup. +# Otherwise there could be a race and the backend may not get woken up. +$node->wait_for_event('client backend', 'nbtree-vacuum-page'); +$node->safe_psql('postgres', "SELECT injection_points_detach('nbtree-vacuum-page');"); +$node->safe_psql('postgres', "SELECT injection_points_wakeup('nbtree-vacuum-page');"); + +# Wait on our second break point. Vacuum should have been forced to backtrack +# and vacuum the first leaf page again to ensure it removed all dead index +# entries. +$node->wait_for_event('client backend', 'nbtree-vacuum-page-backtrack'); + +# Once we wait on our second break point, we're done. Time to tell the backend +# to detach and wake it up. +$node->safe_psql('postgres', "SELECT injection_points_detach('nbtree-vacuum-page-backtrack');"); +$node->safe_psql('postgres', "SELECT injection_points_wakeup('nbtree-vacuum-page-backtrack');"); + +ok($psql_session->quit); + +done_testing(); -- 2.34.1