From: Justin Piszcz <jpiszcz@lucidpixels.com>
To: open list <linux-kernel@vger.kernel.org>, linux-raid@vger.kernel.org
Subject: Re: 3.12: raid-1 mismatch_cnt question
Date: Thu, 7 Nov 2013 05:54:01 -0500 [thread overview]
Message-ID: <CAO9zADxbiW_OBiewAY8JQQjxS51Ydrm8Rj1=MWXCA+Xo9K3=2Q@mail.gmail.com> (raw)
In-Reply-To: <000f01ced948$2fbab140$8f3013c0$@lucidpixels.com>
On Mon, Nov 4, 2013 at 5:25 AM, Justin Piszcz <jpiszcz@lucidpixels.com> wrote:
> 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.
>
Hi,
Could anyone please comment if this is normal/expected behavior?
Thanks,
Justin.
next prev parent reply other threads:[~2013-11-07 10:54 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-04 10:25 3.12: raid-1 mismatch_cnt question Justin Piszcz
2013-11-07 10:54 ` Justin Piszcz [this message]
2013-11-12 0:39 ` Brad Campbell
2013-11-12 9:14 ` Justin Piszcz
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