From 196b72fb9a5556c66f2b012cc4e869175a3049fa Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Fri, 8 Apr 2016 16:48:53 +0900 Subject: [PATCH] Add regression tests for multiple synchronous standbys. Authors: Suraj Kharage, Michael Paquier, Masahiko Sawada, refactored by me Reviewed-By: Kyotaro Horiguchi --- src/test/perl/PostgresNode.pm | 18 ++++ src/test/recovery/t/007_sync_rep.pl | 149 ++++++++++++++++++++++++++++ 2 files changed, 167 insertions(+) create mode 100644 src/test/recovery/t/007_sync_rep.pl diff --git a/src/test/perl/PostgresNode.pm b/src/test/perl/PostgresNode.pm index 2cbd2887ba..e42c1174cb 100644 --- a/src/test/perl/PostgresNode.pm +++ b/src/test/perl/PostgresNode.pm @@ -668,6 +668,24 @@ sub stop =pod +=item $node->reload() + +Reload configuration parameters on the node. + +=cut + +sub reload +{ + my ($self) = @_; + my $port = $self->port; + my $pgdata = $self->data_dir; + my $name = $self->name; + print "### Reloading node \"$name\"\n"; + TestLib::system_log('pg_ctl', '-D', $pgdata, 'reload'); +} + +=pod + =item $node->restart() Wrapper for pg_ctl -w restart diff --git a/src/test/recovery/t/007_sync_rep.pl b/src/test/recovery/t/007_sync_rep.pl new file mode 100644 index 0000000000..c257b6ea16 --- /dev/null +++ b/src/test/recovery/t/007_sync_rep.pl @@ -0,0 +1,149 @@ +# Minimal test testing synchronous replication sync_state transition +use strict; +use warnings; +use PostgresNode; +use TestLib; +use Test::More tests => 8; + +# Query checking sync_priority and sync_state of each standby +my $check_sql = "SELECT application_name, sync_priority, sync_state FROM pg_stat_replication ORDER BY application_name;"; + +# Check that sync_state of each standby is expected. +# If $setting is given, synchronous_standby_names is set to it and +# the configuration file is reloaded before the test. +sub test_sync_state +{ + my ($self, $expected, $msg, $setting) = @_; + + if (defined($setting)) + { + $self->psql('postgres', + "ALTER SYSTEM SET synchronous_standby_names = '$setting';"); + $self->reload; + } + + my $result = $self->safe_psql('postgres', $check_sql); + is($result, $expected, $msg); +} + +# Initialize master node +my $node_master = get_new_node('master'); +$node_master->init(allows_streaming => 1); +$node_master->start; +my $backup_name = 'master_backup'; + +# Take backup +$node_master->backup($backup_name); + +# Create standby1 linking to master +my $node_standby_1 = get_new_node('standby1'); +$node_standby_1->init_from_backup($node_master, $backup_name, + has_streaming => 1); +$node_standby_1->start; + +# Create standby2 linking to master +my $node_standby_2 = get_new_node('standby2'); +$node_standby_2->init_from_backup($node_master, $backup_name, + has_streaming => 1); +$node_standby_2->start; + +# Create standby3 linking to master +my $node_standby_3 = get_new_node('standby3'); +$node_standby_3->init_from_backup($node_master, $backup_name, + has_streaming => 1); +$node_standby_3->start; + +# Check that sync_state is determined correctly when +# synchronous_standby_names is specified in old syntax. +test_sync_state($node_master, qq(standby1|1|sync +standby2|2|potential +standby3|0|async), + 'old syntax of synchronous_standby_names', + 'standby1,standby2'); + +# Check that all the standbys are considered as either sync or +# potential when * is specified in synchronous_standby_names. +# Note that standby1 is chosen as sync standby because +# it's stored in the head of WalSnd array which manages +# all the standbys though they have the same priority. +test_sync_state($node_master, qq(standby1|1|sync +standby2|1|potential +standby3|1|potential), + 'asterisk in synchronous_standby_names', + '*'); + +# Stop and start standbys to rearrange the order of standbys +# in WalSnd array. Now, if standbys have the same priority, +# standby2 is selected preferentially and standby3 is next. +$node_standby_1->stop; +$node_standby_2->stop; +$node_standby_3->stop; + +$node_standby_2->start; +$node_standby_3->start; + +# Specify 2 as the number of sync standbys. +# Check that two standbys are in 'sync' state. +test_sync_state($node_master, qq(standby2|2|sync +standby3|3|sync), + '2 synchronous standbys', + '2(standby1,standby2,standby3)'); + +# Start standby1 +$node_standby_1->start; + +# Create standby4 linking to master +my $node_standby_4 = get_new_node('standby4'); +$node_standby_4->init_from_backup($node_master, $backup_name, + has_streaming => 1); +$node_standby_4->start; + +# Check that standby1 and standby2 whose names appear earlier in +# synchronous_standby_names are considered as sync. Also check that +# standby3 appearing later represents potential, and standby4 is +# in 'async' state because it's not in the list. +test_sync_state($node_master, qq(standby1|1|sync +standby2|2|sync +standby3|3|potential +standby4|0|async), + '2 sync, 1 potential and 1 async'); + +# Check that sync_state of each standby is determined correctly +# when num_sync exceeds the number of names of potential sync standbys +# specified in synchronous_standby_names. +test_sync_state($node_master, qq(standby1|0|async +standby2|4|sync +standby3|3|sync +standby4|1|sync), + 'num_sync exceeds the num of potential sync standbys', + '6(standby4,standby0,standby3,standby2)'); + +# The setting that * comes before another standby name is acceptable +# but does not make sense in most cases. Check that sync_state is +# chosen properly even in case of that setting. +# The priority of standby2 should be 2 because it matches * first. +test_sync_state($node_master, qq(standby1|1|sync +standby2|2|sync +standby3|2|potential +standby4|2|potential), + 'asterisk comes before another standby name', + '2(standby1,*,standby2)'); + +# Check that the setting of '2(*)' chooses standby2 and standby3 that are stored +# earlier in WalSnd array as sync standbys. +test_sync_state($node_master, qq(standby1|1|potential +standby2|1|sync +standby3|1|sync +standby4|1|potential), + 'multiple standbys having the same priority are chosen as sync', + '2(*)'); + +# Stop Standby3 which is considered in 'sync' state. +$node_standby_3->stop; + +# Check that the state of standby1 stored earlier in WalSnd array than +# standby4 is transited from potential to sync. +test_sync_state($node_master, qq(standby1|1|sync +standby2|1|sync +standby4|1|potential), + 'potential standby found earlier in array is promoted to sync');