diff --git a/src/backend/distributed/shared_library_init.c b/src/backend/distributed/shared_library_init.c
index 381ea0000..9d9a18d70 100644
--- a/src/backend/distributed/shared_library_init.c
+++ b/src/backend/distributed/shared_library_init.c
@@ -2716,7 +2716,7 @@ ShowShardsForAppNamePrefixesCheckHook(char **newval, void **extra, GucSource sou
 		}
 
 		char *prefixAscii = pstrdup(appNamePrefix);
-		pg_clean_ascii(prefixAscii);
+		pg_clean_ascii(prefixAscii, MCXT_ALLOC_HUGE);
 
 		if (strcmp(prefixAscii, appNamePrefix) != 0)
 		{