Improve wording of log messages triggered by max_slot_wal_keep_size.

tglsfdc · tglsfdc · commit 551aa6b7b9f3 · 2022-09-29T13:27:48.000-04:00
The one about "terminating process to release replication slot" told you nothing about why that was happening. The one about "invalidating slot because its restart_lsn exceeds max_slot_wal_keep_size" told you what was happening, but violated our message style guideline about keeping the primary message short. Add DETAIL/HINT lines to carry the appropriate detail and make the two cases more uniform. While here, fix bogus test logic in 019_replslot_limit.pl: if it timed out without seeing the expected log message, no test failure would be reported. This is flat broken since commit 549ec20 removed the test counts; even before that it was horribly bad style, since you'd only get told that not all tests had been run. Kyotaro Horiguchi, reviewed by Bertrand Drouvot; test fixes by me Discussion: https://postgr.es/m/20211214.130456.2233153190058148084.horikyota.ntt@gmail.com
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
@@ -1293,8 +1293,12 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlot *s, XLogRecPtr oldestLSN,
 			if (last_signaled_pid != active_pid)
 			{
 				ereport(LOG,
-						(errmsg("terminating process %d to release replication slot \"%s\"",
-								active_pid, NameStr(slotname))));
+						errmsg("terminating process %d to release replication slot \"%s\"",
+							   active_pid, NameStr(slotname)),
+						errdetail("The slot's restart_lsn %X/%X exceeds the limit by %llu bytes.",
+								  LSN_FORMAT_ARGS(restart_lsn),
+								  (unsigned long long) (oldestLSN - restart_lsn)),
+						errhint("You might need to increase max_slot_wal_keep_size."));
 
 				(void) kill(active_pid, SIGTERM);
 				last_signaled_pid = active_pid;
@@ -1331,9 +1335,12 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlot *s, XLogRecPtr oldestLSN,
 			ReplicationSlotRelease();
 
 			ereport(LOG,
-					(errmsg("invalidating slot \"%s\" because its restart_lsn %X/%X exceeds max_slot_wal_keep_size",
-							NameStr(slotname),
-							LSN_FORMAT_ARGS(restart_lsn))));
+					errmsg("invalidating obsolete replication slot \"%s\"",
+						   NameStr(slotname)),
+					errdetail("The slot's restart_lsn %X/%X exceeds the limit by %llu bytes.",
+							  LSN_FORMAT_ARGS(restart_lsn),
+							  (unsigned long long) (oldestLSN - restart_lsn)),
+					errhint("You might need to increase max_slot_wal_keep_size."));
 
 			/* done with this slot for now */
 			break;
diff --git a/src/test/recovery/t/019_replslot_limit.pl b/src/test/recovery/t/019_replslot_limit.pl
@@ -185,8 +185,7 @@
 for (my $i = 0; $i < 10000; $i++)
 {
 	if (find_in_log(
-			$node_primary,
-			"invalidating slot \"rep1\" because its restart_lsn [0-9A-F/]+ exceeds max_slot_wal_keep_size",
+			$node_primary, 'invalidating obsolete replication slot "rep1"',
 			$logstart))
 	{
 		$invalidated = 1;
@@ -379,6 +378,7 @@
 kill 'STOP', $senderpid, $receiverpid;
 advance_wal($node_primary3, 2);
 
+my $msg_logged   = 0;
 my $max_attempts = $PostgreSQL::Test::Utils::timeout_default;
 while ($max_attempts-- >= 0)
 {
@@ -387,11 +387,12 @@
 			"terminating process $senderpid to release replication slot \"rep3\"",
 			$logstart))
 	{
-		ok(1, "walsender termination logged");
+		$msg_logged = 1;
 		last;
 	}
 	sleep 1;
 }
+ok($msg_logged, "walsender termination logged");
 
 # Now let the walsender continue; slot should be killed now.
 # (Must not let walreceiver run yet; otherwise the standby could start another
@@ -402,18 +403,20 @@
 	"lost")
   or die "timed out waiting for slot to be lost";
 
+$msg_logged   = 0;
 $max_attempts = $PostgreSQL::Test::Utils::timeout_default;
 while ($max_attempts-- >= 0)
 {
 	if (find_in_log(
-			$node_primary3,
-			'invalidating slot "rep3" because its restart_lsn', $logstart))
+			$node_primary3, 'invalidating obsolete replication slot "rep3"',
+			$logstart))
 	{
-		ok(1, "slot invalidation logged");
+		$msg_logged = 1;
 		last;
 	}
 	sleep 1;
 }
+ok($msg_logged, "slot invalidation logged");
 
 # Now let the walreceiver continue, so that the node can be stopped cleanly
 kill 'CONT', $receiverpid;

Original file line number	Diff line number	Diff line change
`@@ -185,8 +185,7 @@`
`185`	`185`	`for (my $i = 0; $i < 10000; $i++)`
`186`	`186`	`{`
`187`	`187`	`if (find_in_log(`
`188`		`- $node_primary,`
`189`		`- "invalidating slot \"rep1\" because its restart_lsn [0-9A-F/]+ exceeds max_slot_wal_keep_size",`
	`188`	`+ $node_primary, 'invalidating obsolete replication slot "rep1"',`
`190`	`189`	`$logstart))`
`191`	`190`	`{`
`192`	`191`	`$invalidated = 1;`
`@@ -379,6 +378,7 @@`
`379`	`378`	`kill 'STOP', $senderpid, $receiverpid;`
`380`	`379`	`advance_wal($node_primary3, 2);`
`381`	`380`
	`381`	`+my $msg_logged = 0;`
`382`	`382`	`my $max_attempts = $PostgreSQL::Test::Utils::timeout_default;`
`383`	`383`	`while ($max_attempts-- >= 0)`
`384`	`384`	`{`
`@@ -387,11 +387,12 @@`
`387`	`387`	`"terminating process $senderpid to release replication slot \"rep3\"",`
`388`	`388`	`$logstart))`
`389`	`389`	`{`
`390`		`- ok(1, "walsender termination logged");`
	`390`	`+ $msg_logged = 1;`
`391`	`391`	`last;`
`392`	`392`	`}`
`393`	`393`	`sleep 1;`
`394`	`394`	`}`
	`395`	`+ok($msg_logged, "walsender termination logged");`
`395`	`396`
`396`	`397`	`# Now let the walsender continue; slot should be killed now.`
`397`	`398`	`# (Must not let walreceiver run yet; otherwise the standby could start another`
`@@ -402,18 +403,20 @@`
`402`	`403`	`"lost")`
`403`	`404`	`or die "timed out waiting for slot to be lost";`
`404`	`405`
	`406`	`+$msg_logged = 0;`
`405`	`407`	`$max_attempts = $PostgreSQL::Test::Utils::timeout_default;`
`406`	`408`	`while ($max_attempts-- >= 0)`
`407`	`409`	`{`
`408`	`410`	`if (find_in_log(`
`409`		`- $node_primary3,`
`410`		`- 'invalidating slot "rep3" because its restart_lsn', $logstart))`
	`411`	`+ $node_primary3, 'invalidating obsolete replication slot "rep3"',`
	`412`	`+ $logstart))`
`411`	`413`	`{`
`412`		`- ok(1, "slot invalidation logged");`
	`414`	`+ $msg_logged = 1;`
`413`	`415`	`last;`
`414`	`416`	`}`
`415`	`417`	`sleep 1;`
`416`	`418`	`}`
	`419`	`+ok($msg_logged, "slot invalidation logged");`
`417`	`420`
`418`	`421`	`# Now let the walreceiver continue, so that the node can be stopped cleanly`
`419`	`422`	`kill 'CONT', $receiverpid;`