From b6916ca91c623a892f61cc9d1958c19490eb73ae Mon Sep 17 00:00:00 2001
From: Wang Yuan <wangyuancode@163.com>
Date: Tue, 1 Dec 2020 05:15:14 +0800
Subject: [PATCH] Reset average ttl when empty databases (#8106)

On FLUSHDB or full sync, reset old average TTL stat.
This Stat is incrementally collected by the master over time when it searches for expired keys.
---
 src/db.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/db.c b/src/db.c
index fbbd63748..e51f79eaa 100644
--- a/src/db.c
+++ b/src/db.c
@@ -416,6 +416,9 @@ long long emptyDbGeneric(redisDb *dbarray, int dbnum, int flags, void(callback)(
             dictEmpty(dbarray[j].dict,callback);
             dictEmpty(dbarray[j].expires,callback);
         }
+        /* Because we will start a new database, reset average ttl. */
+        dbarray[j].avg_ttl = 0;
+        dbarray[j].expires_cursor = 0;
     }
 
     /* Post-flush actions */