Fix upper limit of superuser_reserved_connections, add limit for wal_senders

Should be limited to the maximum number of connections excluding
autovacuum workers, not including.

Add similar check for max_wal_senders, which should never be higher than
max_connections.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 94e22da41e1..3a4cef34486 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -759,11 +759,16 @@ PostmasterMain(int argc, char *argv[])
 	/*
 	 * Check for invalid combinations of GUC settings.
 	 */
-	if (ReservedBackends >= MaxBackends)
+	if (ReservedBackends >= MaxConnections)
 	{
 		write_stderr("%s: superuser_reserved_connections must be less than max_connections\n", progname);
 		ExitPostmaster(1);
 	}
+	if (max_wal_senders >= MaxConnections)
+	{
+		write_stderr("%s: max_wal_senders must be less than max_connections\n", progname);
+		ExitPostmaster(1);
+	}
 	if (XLogArchiveMode && wal_level == WAL_LEVEL_MINIMAL)
 		ereport(ERROR,
 				(errmsg("WAL archival (archive_mode=on) requires wal_level \"archive\" or \"hot_standby\"")));