From: Heinz Mauelshagen <heinzm@redhat.com>
To: device-mapper development <dm-devel@redhat.com>
Subject: Re: dm-cache: dirty state of blocks in writethrough mode
Date: Tue, 23 Jul 2013 15:26:08 +0200 [thread overview]
Message-ID: <51EE8470.6070302@redhat.com> (raw)
In-Reply-To: <C91EDD5251EDF44CB434B1039B0DEEB82A8D0762@SACEXCMBX02-PRD.hq.netapp.com>
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On 07/23/2013 08:44 AM, Vijarnia, Anil wrote:
> Hello,
> In Documentation/cache.txt, section 'Updating on-disk metadata' mentions that "If the system crashes all cache blocks will be assumed dirty when restarted".
> I am assuming that the above line is relevant for writeback mode only, and in writethrough mode the cache will always be coherent after a crash.
> Can someone confirm/reject this assumption?
That's correct
Reason being that the cache never holds any dirty pages in writethrough
mode.
-- lvmguy
>
> Thanks
>
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> --
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
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next prev parent reply other threads:[~2013-07-23 13:26 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-23 6:44 dm-cache: dirty state of blocks in writethrough mode Vijarnia, Anil
2013-07-23 13:26 ` Heinz Mauelshagen [this message]
2013-07-24 10:24 ` Kumar amit mehta
2013-07-24 17:05 ` Heinz Mauelshagen
2013-07-24 13:02 ` Kumar amit mehta
2013-07-25 10:45 ` Heinz Mauelshagen
2013-07-26 2:45 ` Kumar amit mehta
2013-07-26 11:14 ` Heinz Mauelshagen
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