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From: NeilBrown <neilb@suse.de>
To: stkoupr <p.kouril@cra.cz>
Cc: linux-raid@vger.kernel.org
Subject: Re: multi-threaded raid5
Date: Tue, 7 Apr 2015 11:11:57 +1000	[thread overview]
Message-ID: <20150407111157.2200fb0b@notabene.brown> (raw)
In-Reply-To: <551AD6AE.4030607@cra.cz>

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On Tue, 31 Mar 2015 19:17:34 +0200 stkoupr <p.kouril@cra.cz> wrote:

> Hi,
> 
> We are testing write performance of md raid5 with SSD array and we are 
> hitting limit which I understand is caused by writes being handled in 
> single thread (md0_raid5 process is eating 100% of 1 CPU core when the 
> test is running). I understood that there is some work in progress which 
> should make write handling multi-threaded. I'd like to ask about the 
> status of this work, is it still in progress or planned?
> 
> Regards,
> Prema
> --
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See /sys/block/mdXXX/md/group_thread_cnt

Set it to a bigger number, get more threads.

Requires 3.12 or later.

NeilBrown

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  reply	other threads:[~2015-04-07  1:11 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-31 17:17 multi-threaded raid5 stkoupr
2015-04-07  1:11 ` NeilBrown [this message]
2015-04-07  4:34   ` Thomas Fjellstrom

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