From: NeilBrown <neilb@suse.de>
To: Milan Broz <gmazyland@gmail.com>
Cc: Phil Turmel <philip@turmel.org>,
Christoph Anton Mitterer <calestyo@scientia.net>,
linux-raid@vger.kernel.org
Subject: Re: some general questions on RAID
Date: Mon, 8 Jul 2013 14:53:16 +1000 [thread overview]
Message-ID: <20130708145316.4486d0dc@notabene.brown> (raw)
In-Reply-To: <51D9A7CF.6000700@gmail.com>
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On Sun, 07 Jul 2013 19:39:27 +0200 Milan Broz <gmazyland@gmail.com> wrote:
> So if you have multiple IOs submitted in parallel from *different* CPUs,
> they are processed in parallel.
>
> If you have MD over dmcrypt, this can cause problem that MD sumbits all IOs
> with the same cpu context and dmcrypt cannot run it in parallel.
For RAID1 and RAID10 this isn't true any more.
Commit f54a9d0e59c4bea3db733921ca9147612a6f292c
in 3.6 changed this for RAID1 and a similar commit did for RAID10.
RAID4/5/6 still submit from a single thread as you say.
NeilBrown
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next prev parent reply other threads:[~2013-07-08 4:53 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-04 18:30 some general questions on RAID Christoph Anton Mitterer
2013-07-04 22:07 ` Phil Turmel
2013-07-04 23:34 ` Christoph Anton Mitterer
2013-07-08 4:48 ` NeilBrown
2013-07-06 1:33 ` Christoph Anton Mitterer
2013-07-06 8:52 ` Stan Hoeppner
2013-07-06 15:15 ` Christoph Anton Mitterer
2013-07-07 16:51 ` Stan Hoeppner
2013-07-07 17:39 ` Milan Broz
2013-07-07 18:01 ` Christoph Anton Mitterer
2013-07-07 18:50 ` Milan Broz
2013-07-07 20:51 ` Christoph Anton Mitterer
2013-07-08 5:40 ` Milan Broz
2013-07-08 4:53 ` NeilBrown [this message]
2013-07-08 5:25 ` Milan Broz
2013-07-05 1:13 ` Brad Campbell
2013-07-05 1:39 ` Sam Bingner
2013-07-05 3:06 ` Brad Campbell
2013-07-06 1:23 ` some general questions on RAID (OT) Christoph Anton Mitterer
2013-07-06 6:23 ` Sam Bingner
2013-07-06 15:11 ` Christoph Anton Mitterer
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