From: "Justin Piszcz" <jpiszcz@lucidpixels.com>
To: <linux-kernel@vger.kernel.org>, <linux-raid@vger.kernel.org>
Subject: 3.12: raid-1 mismatch_cnt question
Date: Mon, 4 Nov 2013 05:25:28 -0500 [thread overview]
Message-ID: <000f01ced948$2fbab140$8f3013c0$@lucidpixels.com> (raw)
Hi,
I run two SSDs in a RAID-1 configuration and I have a swap partition on a
third SSD. Over time, the mismatch_cnt between the two devices grows higher
and higher.
Once a week, I run a check and repair against the md devices to help bring
the mismatch_cnt down. When I run the check and repair, the system is live
so there are various logs/processes writing to disk. The system also has
ECC memory and there are no errors reported.
The following graph is the mismatch_cnt from June 2013 to current; each drop
represents a check+repair. In September, I dropped the kernel/vm caches
before running check/repair and that seemed to help a bit.
http://home.comcast.net/~jpiszcz/20131104/md_raid_mismatch_cnt.png
My question is: is this normal or should the mismatch_cnt always be 0 unless
there is a HW or md/driver issue?
Justin.
next reply other threads:[~2013-11-04 10:25 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-04 10:25 Justin Piszcz [this message]
2013-11-07 10:54 ` 3.12: raid-1 mismatch_cnt question Justin Piszcz
2013-11-12 0:39 ` Brad Campbell
2013-11-12 9:14 ` Justin Piszcz
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