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From: Thomas Fjellstrom <thomas@fjellstrom.ca>
To: NeilBrown <neilb@suse.de>, linux-raid@vger.kernel.org
Subject: Re: multi-threaded raid5
Date: Mon, 06 Apr 2015 22:34:15 -0600	[thread overview]
Message-ID: <1659926.GihAnxuuSt@balsa> (raw)
In-Reply-To: <20150407111157.2200fb0b@notabene.brown>

On Tue 07 Apr 2015 11:11:57 AM NeilBrown wrote:
> 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
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> See /sys/block/mdXXX/md/group_thread_cnt
> 
> Set it to a bigger number, get more threads.
> 
> Requires 3.12 or later.

What does it mean when that property is set to 0?

> NeilBrown

-- 
Thomas Fjellstrom
thomas@fjellstrom.ca

      reply	other threads:[~2015-04-07  4:34 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
2015-04-07  4:34   ` Thomas Fjellstrom [this message]

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