contrib/test_decoding/t/001_repl_stats.pl

   1
   2 # Copyright (c) 2021-2022, PostgreSQL Global Development Group
   3
   4 # Test replication statistics data in pg_stat_replication_slots is sane after
   5 # drop replication slot and restart.
   6 use strict;
   7 use warnings;
   8 use File::Path qw(rmtree);
   9 use PostgreSQL::Test::Cluster;
  10 use PostgreSQL::Test::Utils;
  11 use Test::More tests => 2;
  12
  13 # Test set-up
  14 my $node = PostgreSQL::Test::Cluster->new('test');
  15 $node->init(allows_streaming => 'logical');
  16 $node->append_conf('postgresql.conf', 'synchronous_commit = on');
  17 $node->start;
  18
  19 # Check that replication slot stats are expected.
  20 sub test_slot_stats
  21 {
  22         local $Test::Builder::Level = $Test::Builder::Level + 1;
  23
  24         my ($node, $expected, $msg) = @_;
  25
  26         my $result = $node->safe_psql(
  27                 'postgres', qq[
  28                 SELECT slot_name, total_txns > 0 AS total_txn,
  29                            total_bytes > 0 AS total_bytes
  30                            FROM pg_stat_replication_slots
  31                            ORDER BY slot_name]);
  32         is($result, $expected, $msg);
  33 }
  34
  35 # Create table.
  36 $node->safe_psql('postgres', "CREATE TABLE test_repl_stat(col1 int)");
  37
  38 # Create replication slots.
  39 $node->safe_psql(
  40         'postgres', qq[
  41         SELECT pg_create_logical_replication_slot('regression_slot1', 'test_decoding');
  42         SELECT pg_create_logical_replication_slot('regression_slot2', 'test_decoding');
  43         SELECT pg_create_logical_replication_slot('regression_slot3', 'test_decoding');
  44         SELECT pg_create_logical_replication_slot('regression_slot4', 'test_decoding');
  45 ]);
  46
  47 # Insert some data.
  48 $node->safe_psql('postgres',
  49         "INSERT INTO test_repl_stat values(generate_series(1, 5));");
  50
  51 $node->safe_psql(
  52         'postgres', qq[
  53         SELECT data FROM pg_logical_slot_get_changes('regression_slot1', NULL,
  54         NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
  55         SELECT data FROM pg_logical_slot_get_changes('regression_slot2', NULL,
  56         NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
  57         SELECT data FROM pg_logical_slot_get_changes('regression_slot3', NULL,
  58         NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
  59         SELECT data FROM pg_logical_slot_get_changes('regression_slot4', NULL,
  60         NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
  61 ]);
  62
  63 # Wait for the statistics to be updated.
  64 $node->poll_query_until(
  65         'postgres', qq[
  66         SELECT count(slot_name) >= 4 FROM pg_stat_replication_slots
  67         WHERE slot_name ~ 'regression_slot'
  68         AND total_txns > 0 AND total_bytes > 0;
  69 ]) or die "Timed out while waiting for statistics to be updated";
  70
  71 # Test to drop one of the replication slot and verify replication statistics data is
  72 # fine after restart.
  73 $node->safe_psql('postgres',
  74         "SELECT pg_drop_replication_slot('regression_slot4')");
  75
  76 $node->stop;
  77 $node->start;
  78
  79 # Verify statistics data present in pg_stat_replication_slots are sane after
  80 # restart.
  81 test_slot_stats(
  82         $node,
  83         qq(regression_slot1|t|t
  84 regression_slot2|t|t
  85 regression_slot3|t|t),
  86         'check replication statistics are updated');
  87
  88 # Test to remove one of the replication slots and adjust
  89 # max_replication_slots accordingly to the number of slots. This leads
  90 # to a mismatch between the number of slots present in the stats file and the
  91 # number of stats present in the shared memory, simulating the scenario for
  92 # drop slot message lost by the statistics collector process. We verify
  93 # replication statistics data is fine after restart.
  94
  95 $node->stop;
  96 my $datadir           = $node->data_dir;
  97 my $slot3_replslotdir = "$datadir/pg_replslot/regression_slot3";
  98
  99 rmtree($slot3_replslotdir);
 100
 101 $node->append_conf('postgresql.conf', 'max_replication_slots = 2');
 102 $node->start;
 103
 104 # Verify statistics data present in pg_stat_replication_slots are sane after
 105 # restart.
 106 test_slot_stats(
 107         $node,
 108         qq(regression_slot1|t|t
 109 regression_slot2|t|t),
 110         'check replication statistics after removing the slot file');
 111
 112 # cleanup
 113 $node->safe_psql('postgres', "DROP TABLE test_repl_stat");
 114 $node->safe_psql('postgres',
 115         "SELECT pg_drop_replication_slot('regression_slot1')");
 116 $node->safe_psql('postgres',
 117         "SELECT pg_drop_replication_slot('regression_slot2')");
 118
 119 # shutdown
 120 $node->stop;