test-archive-restartpoint-v1.patch

Author:     Noah Misch <noah@leadboat.com>
Commit:     Noah Misch <noah@leadboat.com>

    Test restartpoints in archive recovery.
    
    v14 commit 1f95181b44c843729caaa688f74babe9403b5850 and its v13 equivalent
    caused timing-dependent failures in archive recovery, at restartpoints.  The
    symptom was "invalid magic number 0000 in log segment X, offset 0",
    "unexpected pageaddr X in log segment Y, offset 0" [X < Y], or an assertion
    failure.  Commit FIXME and predecessors back-patched v15 changes to fix that.
    This test reproduces the problem probabilistically, typically in less than
    1000 iterations of the test.  Hence, buildfarm and CI runs would have surfaced
    enough failures to get attention within a day.  Back-patch to v13 (all
    supported versions).
    
    Reported by Arun Thirupathi.  Reviewed by FIXME.
    
    Discussion: https://postgr.es/m/20250306193013.36.nmisch@google.com

diff --git a/src/test/recovery/meson.build b/src/test/recovery/meson.build
index 057bcde..cb98376 100644
--- a/src/test/recovery/meson.build
+++ b/src/test/recovery/meson.build
@@ -53,6 +53,7 @@ tests += {
       't/042_low_level_backup.pl',
       't/043_no_contrecord_switch.pl',
       't/044_invalidate_inactive_slots.pl',
+      't/045_archive_restartpoint.pl',
     ],
   },
 }
diff --git a/src/test/recovery/t/045_archive_restartpoint.pl b/src/test/recovery/t/045_archive_restartpoint.pl
new file mode 100644
index 0000000..b143bc4
--- /dev/null
+++ b/src/test/recovery/t/045_archive_restartpoint.pl
@@ -0,0 +1,57 @@
+
+# Copyright (c) 2024-2025, PostgreSQL Global Development Group
+
+# Test restartpoints during archive recovery.
+use strict;
+use warnings;
+
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+my $archive_max_mb = 320;
+my $wal_segsize = 1;
+
+# Initialize primary node
+my $node_primary = PostgreSQL::Test::Cluster->new('primary');
+$node_primary->init(
+	has_archiving => 1,
+	allows_streaming => 1,
+	extra => [ '--wal-segsize' => $wal_segsize ]);
+$node_primary->start;
+my $backup_name = 'my_backup';
+$node_primary->backup($backup_name);
+
+$node_primary->safe_psql('postgres',
+	('DO $$BEGIN FOR i IN 1..' . $archive_max_mb / $wal_segsize)
+	  . ' LOOP CHECKPOINT; PERFORM pg_switch_wal(); END LOOP; END$$;');
+
+# Force archiving of WAL file containing recovery target
+my $until_lsn = $node_primary->lsn('write');
+$node_primary->safe_psql('postgres', "SELECT pg_switch_wal()");
+$node_primary->stop;
+
+# Archive recovery
+my $node_restore = PostgreSQL::Test::Cluster->new('restore');
+$node_restore->init_from_backup($node_primary, $backup_name,
+	has_restoring => 1);
+$node_restore->append_conf('postgresql.conf',
+	"recovery_target_lsn = '$until_lsn'");
+$node_restore->append_conf('postgresql.conf',
+	'recovery_target_action = pause');
+$node_restore->append_conf('postgresql.conf',
+	'max_wal_size = ' . 2 * $wal_segsize);
+$node_restore->append_conf('postgresql.conf', 'log_checkpoints = on');
+
+$node_restore->start;
+
+# Wait until restore has replayed enough data
+my $caughtup_query =
+  "SELECT '$until_lsn'::pg_lsn <= pg_last_wal_replay_lsn()";
+$node_restore->poll_query_until('postgres', $caughtup_query)
+  or die "Timed out while waiting for restore to catch up";
+
+$node_restore->stop;
+ok(1, 'restore caught up');
+
+done_testing();