Hi,
Attached patch covers a case where TLI in the filename for a
record being read is different from where it belongs to. In other
words, it covers following case noted in StartupXLOG():
/*
* EndOfLogTLI is the TLI in the filename of the XLOG segment containing
* the end-of-log. It could be different from the timeline that EndOfLog
* nominally belongs to, if there was a timeline switch in that segment,
* and we were reading the old WAL from a segment belonging to a higher
* timeline.
*/
EndOfLogTLI = xlogreader->seg.ws_tli;
Test tried to set recovery target just before the end-of-recovery WAL
record. Unfortunately, the test couldn't directly verify EndOfLogTLI
!= replayTLI case, I am not sure how to do that -- any suggestions
will be greatly appreciated. Perhaps, having this test is good to
improve xlog.c test coverage. Also, if you see in other angle test
covers a case where recovery_target_lsn and
recovery_target_inclusive=off which doesn't exist as of now and that
is the reason I have added this test to 003_recovery_targets.pl file.
Thoughts? Suggestions?
--
Regards,
Amul Sul
EDB: http://www.enterprisedb.com
From 4e2bbb37d4874c910494ba221c7be7e02a29c8c1 Mon Sep 17 00:00:00 2001
From: Amul Sul <amul.sul@enterprisedb.com>
Date: Mon, 22 Nov 2021 09:16:51 -0500
Subject: [PATCH v1] TAP test for EndOfLogTLI
---
src/test/recovery/t/003_recovery_targets.pl | 55 ++++++++++++++++++++-
1 file changed, 54 insertions(+), 1 deletion(-)
diff --git a/src/test/recovery/t/003_recovery_targets.pl b/src/test/recovery/t/003_recovery_targets.pl
index 0d0636b85c0..b0d59a181e4 100644
--- a/src/test/recovery/t/003_recovery_targets.pl
+++ b/src/test/recovery/t/003_recovery_targets.pl
@@ -6,7 +6,7 @@ use strict;
use warnings;
use PostgreSQL::Test::Cluster;
use PostgreSQL::Test::Utils;
-use Test::More tests => 9;
+use Test::More tests => 10;
use Time::HiRes qw(usleep);
# Create and test a standby from given backup, with a certain recovery target.
@@ -182,3 +182,56 @@ $logfile = slurp_file($node_standby->logfile());
ok( $logfile =~
qr/FATAL: .* recovery ended before configured recovery target was reached/,
'recovery end before target reached is a fatal error');
+
+# Test to cover a case where that we are looking for WAL record that ought to be
+# in for e.g 000000010000000000000001 we don't find it; instead we find
+# 000000020000000000000003 because of various reasons such as there was a
+# timeline switch in that segment, and we were reading the old WAL from a
+# segment belonging to a higher timeline or our recovery target timeline is 2,
+# or something that has 2 in its history.
+
+# Insert few more data to primary
+$node_primary->safe_psql('postgres',
+ "INSERT INTO tab_int VALUES (generate_series(6001,7000))");
+my $lsn6 = $node_primary->safe_psql('postgres',
+ "SELECT pg_current_wal_lsn()");
+
+# Setup new standby and enable WAL archiving to archive WAL files at the same
+# location as the primary.
+my $archive_cmd = $node_primary->safe_psql('postgres',
+ "SELECT current_setting('archive_command')");
+$node_standby = PostgreSQL::Test::Cluster->new('standby_9');
+$node_standby->init_from_backup(
+ $node_primary, 'my_backup',
+ has_streaming => 1);
+$node_standby->append_conf(
+ 'postgresql.conf', qq(
+archive_mode = on
+archive_command = '$archive_cmd'
+));
+$node_standby->start;
+# Wait until necessary replay has been done on standby
+$node_primary->wait_for_catchup($node_standby, 'replay',
+ $node_primary->lsn('write'));
+$node_standby->promote;
+$node_standby->safe_psql('postgres',
+ "INSERT INTO tab_int VALUES (generate_series(7001,8000))");
+# Force archiving of WAL file
+$node_standby->safe_psql('postgres', "SELECT pg_switch_wal()");
+$node_standby->stop;
+
+# Another standby whose recovery target lsn will be in the WAL file has
+# a different TLI than the target LSN belongs to.
+$node_standby = PostgreSQL::Test::Cluster->new('standby_10');
+$node_standby->init_from_backup(
+ $node_primary, 'my_backup',
+ has_restoring => 1);
+$node_standby->append_conf(
+ 'postgresql.conf', qq(
+recovery_target_lsn = '$lsn6'
+recovery_target_inclusive = off
+));
+$node_standby->start;
+my $result = $node_standby->safe_psql('postgres',
+ "SELECT count(*) FROM tab_int");
+is($result, '7000', "check standby content before timeline switch $lsn6");
--
2.18.0
