diff --git a/modules/proxy/mod_proxy_balancer.c b/modules/proxy/mod_proxy_balancer.c
index 42fd97b125..347481a323 100644
--- a/modules/proxy/mod_proxy_balancer.c
+++ b/modules/proxy/mod_proxy_balancer.c
@@ -908,7 +908,7 @@ static int balancer_post_config(apr_pool_t *pconf, apr_pool_t *plog,
             continue;
         }
         if (conf->bal_persist) {
-            type = AP_SLOTMEM_TYPE_PERSIST;
+            type = AP_SLOTMEM_TYPE_PERSIST | AP_SLOTMEM_TYPE_CLEARINUSE;
         } else {
             type = 0;
         }