diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index a4e5d0886a1..62285792eca 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -3210,7 +3210,7 @@ static struct config_int ConfigureNamesInt[] =
 			GUC_UNIT_BYTE
 		},
 		&pgstat_track_activity_query_size,
-		1024, 100, 102400,
+		1024, 100, 1048576,
 		NULL, NULL, NULL
 	},