--- linux-4.18/fs/ext4/mballoc.c	2019-11-28 14:55:26.500545920 +0300
+++ linux-4.18/fs/ext4/mballoc.c	2019-11-28 14:53:18.600086008 +0300
@@ -2060,7 +2060,15 @@ static int ext4_mb_good_group(struct
 
 	/* We only do this if the grp has never been initialized */
 	if (unlikely(EXT4_MB_GRP_NEED_INIT(grp))) {
-		int ret = ext4_mb_init_group(ac->ac_sb, group, GFP_NOFS);
+		int ret;
+
+		/* cr=0/1 is a very optimistic search to find large
+		 * good chunks almost for free. if buddy data is
+		 * not ready, then this optimization makes no sense */
+
+		if (cr < 2)
+			return 0;
+		ret = ext4_mb_init_group(ac->ac_sb, group, GFP_NOFS);
 		if (ret)
 			return ret;
 	}