1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
# Copyright (c) 2025, PostgreSQL Global Development Group
#
# This test verifies the case when the physical slot is advanced during
# checkpoint. The test checks that the physical slot's restart_lsn still refers
# to an existed WAL segment after immediate restart.
#
use strict;
use warnings FATAL => 'all';
use PostgreSQL::Test::Cluster;
use PostgreSQL::Test::Utils;
use Test::More;
if ($ENV{enable_injection_points} ne 'yes')
{
plan skip_all => 'Injection points not supported by this build';
}
my ($node, $result);
$node = PostgreSQL::Test::Cluster->new('mike');
$node->init;
$node->append_conf('postgresql.conf', "wal_level = 'replica'");
$node->start;
# Check if the extension injection_points is available, as it may be
# possible that this script is run with installcheck, where the module
# would not be installed by default.
if (!$node->check_extension('injection_points'))
{
plan skip_all => 'Extension injection_points not installed';
}
$node->safe_psql('postgres', q(CREATE EXTENSION injection_points));
# Create a physical replication slot.
$node->safe_psql('postgres',
q{select pg_create_physical_replication_slot('slot_physical', true)});
# Advance slot to the current position, just to have everything "valid".
$node->safe_psql('postgres',
q{select pg_replication_slot_advance('slot_physical', pg_current_wal_lsn())}
);
# Run checkpoint to flush current state to disk and set a baseline.
$node->safe_psql('postgres', q{checkpoint});
# Insert 2M rows; that's about 260MB (~20 segments) worth of WAL.
$node->advance_wal(20);
# Advance slot to the current position, just to have everything "valid".
$node->safe_psql('postgres',
q{select pg_replication_slot_advance('slot_physical', pg_current_wal_lsn())}
);
# Run another checkpoint to set a new restore LSN.
$node->safe_psql('postgres', q{checkpoint});
# Another 2M rows; that's about 260MB (~20 segments) worth of WAL.
$node->advance_wal(20);
my $restart_lsn_init = $node->safe_psql('postgres',
q{select restart_lsn from pg_replication_slots where slot_name = 'slot_physical'}
);
chomp($restart_lsn_init);
note("restart lsn before checkpoint: $restart_lsn_init");
# Run another checkpoint, this time in the background, and make it wait
# on the injection point) so that the checkpoint stops right before
# removing old WAL segments.
note('starting checkpoint');
my $checkpoint = $node->background_psql('postgres');
$checkpoint->query_safe(
q{select injection_points_attach('checkpoint-before-old-wal-removal','wait')}
);
$checkpoint->query_until(
qr/starting_checkpoint/,
q(\echo starting_checkpoint
checkpoint;
\q
));
# Wait until the checkpoint stops right before removing WAL segments.
note('waiting for injection_point');
$node->wait_for_event('checkpointer', 'checkpoint-before-old-wal-removal');
note('injection_point is reached');
# OK, we're in the right situation: time to advance the physical slot, which
# recalculates the required LSN and then unblock the checkpoint, which
# removes the WAL still needed by the physical slot.
$node->safe_psql('postgres',
q{select pg_replication_slot_advance('slot_physical', pg_current_wal_lsn())}
);
# Continue the checkpoint.
$node->safe_psql('postgres',
q{select injection_points_wakeup('checkpoint-before-old-wal-removal')});
my $restart_lsn_old = $node->safe_psql('postgres',
q{select restart_lsn from pg_replication_slots where slot_name = 'slot_physical'}
);
chomp($restart_lsn_old);
note("restart lsn before stop: $restart_lsn_old");
# Abruptly stop the server (1 second should be enough for the checkpoint
# to finish; it would be better).
$node->stop('immediate');
$node->start;
# Get the restart_lsn of the slot right after restarting.
my $restart_lsn = $node->safe_psql('postgres',
q{select restart_lsn from pg_replication_slots where slot_name = 'slot_physical'}
);
chomp($restart_lsn);
note("restart lsn: $restart_lsn");
# Get the WAL segment name for the slot's restart_lsn.
my $restart_lsn_segment = $node->safe_psql('postgres',
"SELECT pg_walfile_name('$restart_lsn'::pg_lsn)");
chomp($restart_lsn_segment);
# Check if the required wal segment exists.
note("required by slot segment name: $restart_lsn_segment");
my $datadir = $node->data_dir;
ok( -f "$datadir/pg_wal/$restart_lsn_segment",
"WAL segment $restart_lsn_segment for physical slot's restart_lsn $restart_lsn exists"
);
done_testing();
|
