Redis sentinel 在 raid-check 运行时进入 TILT 模式？

Question

我正在使用 redis sentinel (Redis v3.0.7)，一切正常。但是在 /var/log/sentinel.log 每个星期日凌晨 1:00 - 4:29 进入了 TILT 模式:

4036:X 12 Nov 01:03:16.607 # +tilt #tilt mode entered
4036:X 12 Nov 01:03:46.622 # -tilt #tilt mode exited
4036:X 12 Nov 01:07:20.246 # +tilt #tilt mode entered
4036:X 12 Nov 01:07:50.401 # -tilt #tilt mode exited
.....
4036:X 12 Nov 04:29:13.825 # +tilt #tilt mode entered
4036:X 12 Nov 04:29:43.860 # -tilt #tilt mode exited

当时我检查了一下，发现 raid_check 也在同时运行:

cat /etc/cron.d/raid-check
Run system wide raid-check once a week on Sunday at 1am by default
0 1 * * Sun root /usr/sbin/raid-check

我不知道为什么。

Answer 1

From the docs:

However if the computer time changes in an unexpected way, or if the computer is very busy, or the process blocked for some reason, Sentinel may start to behave in an unexpected way.

听起来 Redis 注意到服务器由于 RAID 重建而负载过重，并切换到倾斜模式，因此它不会提供不正确的数据，这是所需的行为。