Add 18 new recovery TAP tests

Add new tests for physical repl slots and hot standby feedback.

Craig Ringer, reviewed by Aleksander Alekseev and Simon Riggs

src/test/recovery/t/001_stream_rep.pl

@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 4;
+use Test::More tests => 22;
 
 # Initialize master node
 my $node_master = get_new_node('master');
@@ -58,3 +58,106 @@ is($node_standby_1->psql('postgres', 'INSERT INTO tab_int VALUES (1)'),
 	3, 'read-only queries on standby 1');
 is($node_standby_2->psql('postgres', 'INSERT INTO tab_int VALUES (1)'),
 	3, 'read-only queries on standby 2');
+
+diag "switching to physical replication slot";
+# Switch to using a physical replication slot. We can do this without a new
+# backup since physical slots can go backwards if needed. Do so on both
+# standbys. Since we're going to be testing things that affect the slot state,
+# also increase the standby feedback interval to ensure timely updates.
+my ($slotname_1, $slotname_2) = ('standby_1', 'standby_2');
+$node_master->append_conf('postgresql.conf', "max_replication_slots = 4\n");
+$node_master->restart;
+is($node_master->psql('postgres', qq[SELECT pg_create_physical_replication_slot('$slotname_1');]), 0, 'physical slot created on master');
+$node_standby_1->append_conf('recovery.conf', "primary_slot_name = $slotname_1\n");
+$node_standby_1->append_conf('postgresql.conf', "wal_receiver_status_interval = 1\n");
+$node_standby_1->append_conf('postgresql.conf', "max_replication_slots = 4\n");
+$node_standby_1->restart;
+is($node_standby_1->psql('postgres', qq[SELECT pg_create_physical_replication_slot('$slotname_2');]), 0, 'physical slot created on intermediate replica');
+$node_standby_2->append_conf('recovery.conf', "primary_slot_name = $slotname_2\n");
+$node_standby_2->append_conf('postgresql.conf', "wal_receiver_status_interval = 1\n");
+$node_standby_2->restart;
+
+sub get_slot_xmins
+{
+	my ($node, $slotname) = @_;
+	my $slotinfo = $node->slot($slotname);
+	return ($slotinfo->{'xmin'}, $slotinfo->{'catalog_xmin'});
+}
+
+# There's no hot standby feedback and there are no logical slots on either peer
+# so xmin and catalog_xmin should be null on both slots.
+my ($xmin, $catalog_xmin) = get_slot_xmins($node_master, $slotname_1);
+is($xmin, '', 'non-cascaded slot xmin null with no hs_feedback');
+is($catalog_xmin, '', 'non-cascaded slot xmin null with no hs_feedback');
+
+($xmin, $catalog_xmin) = get_slot_xmins($node_standby_1, $slotname_2);
+is($xmin, '', 'cascaded slot xmin null with no hs_feedback');
+is($catalog_xmin, '', 'cascaded slot xmin null with no hs_feedback');
+
+# Replication still works?
+$node_master->safe_psql('postgres', 'CREATE TABLE replayed(val integer);');
+
+sub replay_check
+{
+	my $newval = $node_master->safe_psql('postgres', 'INSERT INTO replayed(val) SELECT coalesce(max(val),0) + 1 AS newval FROM replayed RETURNING val');
+	$node_master->wait_for_catchup($node_standby_1, 'replay', $node_master->lsn('insert'));
+	$node_standby_1->wait_for_catchup($node_standby_2, 'replay', $node_standby_1->lsn('replay'));
+	$node_standby_1->safe_psql('postgres', qq[SELECT 1 FROM replayed WHERE val = $newval])
+		or die "standby_1 didn't replay master value $newval";
+	$node_standby_2->safe_psql('postgres', qq[SELECT 1 FROM replayed WHERE val = $newval])
+		or die "standby_2 didn't replay standby_1 value $newval";
+}
+
+replay_check();
+
+diag "enabling hot_standby_feedback";
+# Enable hs_feedback. The slot should gain an xmin. We set the status interval
+# so we'll see the results promptly.
+$node_standby_1->safe_psql('postgres', 'ALTER SYSTEM SET hot_standby_feedback = on;');
+$node_standby_1->reload;
+$node_standby_2->safe_psql('postgres', 'ALTER SYSTEM SET hot_standby_feedback = on;');
+$node_standby_2->reload;
+replay_check();
+sleep(2);
+
+($xmin, $catalog_xmin) = get_slot_xmins($node_master, $slotname_1);
+isnt($xmin, '', 'non-cascaded slot xmin non-null with hs feedback');
+is($catalog_xmin, '', 'non-cascaded slot xmin still null with hs_feedback');
+
+($xmin, $catalog_xmin) = get_slot_xmins($node_standby_1, $slotname_2);
+isnt($xmin, '', 'cascaded slot xmin non-null with hs feedback');
+is($catalog_xmin, '', 'cascaded slot xmin still null with hs_feedback');
+
+diag "doing some work to advance xmin";
+for my $i (10000..11000) {
+	$node_master->safe_psql('postgres', qq[INSERT INTO tab_int VALUES ($i);]);
+}
+$node_master->safe_psql('postgres', 'VACUUM;');
+$node_master->safe_psql('postgres', 'CHECKPOINT;');
+
+my ($xmin2, $catalog_xmin2) = get_slot_xmins($node_master, $slotname_1);
+diag "new xmin $xmin2, old xmin $xmin";
+isnt($xmin2, $xmin, 'non-cascaded slot xmin with hs feedback has changed');
+is($catalog_xmin2, '', 'non-cascaded slot xmin still null with hs_feedback unchanged');
+
+($xmin2, $catalog_xmin2) = get_slot_xmins($node_standby_1, $slotname_2);
+diag "new xmin $xmin2, old xmin $xmin";
+isnt($xmin2, $xmin, 'cascaded slot xmin with hs feedback has changed');
+is($catalog_xmin2, '', 'cascaded slot xmin still null with hs_feedback unchanged');
+
+diag "disabling hot_standby_feedback";
+# Disable hs_feedback. Xmin should be cleared.
+$node_standby_1->safe_psql('postgres', 'ALTER SYSTEM SET hot_standby_feedback = off;');
+$node_standby_1->reload;
+$node_standby_2->safe_psql('postgres', 'ALTER SYSTEM SET hot_standby_feedback = off;');
+$node_standby_2->reload;
+replay_check();
+sleep(2);
+
+($xmin, $catalog_xmin) = get_slot_xmins($node_master, $slotname_1);
+is($xmin, '', 'non-cascaded slot xmin null with hs feedback reset');
+is($catalog_xmin, '', 'non-cascaded slot xmin still null with hs_feedback reset');
+
+($xmin, $catalog_xmin) = get_slot_xmins($node_standby_1, $slotname_2);
+is($xmin, '', 'cascaded slot xmin null with hs feedback reset');
+is($catalog_xmin, '', 'cascaded slot xmin still null with hs_feedback reset');