diff --git a/src/server.c b/src/server.c
index def012728..9463882fe 100644
--- a/src/server.c
+++ b/src/server.c
@@ -5299,6 +5299,10 @@ static void srv_cleanup_connections(struct server *srv)
 	int did_remove;
 	int i;
 
+	/* nothing to do if pool-max-conn is null */
+	if (!srv->max_idle_conns)
+		return;
+
 	/* check all threads starting with ours */
 	for (i = tid;;) {
 		did_remove = 0;