From: Wayne Conrad <wayne@databill.com>
To: pgsql-performance@postgresql.org
Subject: Re: Linux I/O schedulers - CFQ & random seeks
Date: Fri, 04 Mar 2011 11:03:36 -0700
Message-ID: <4D712978.60504@databill.com> (raw)
In-Reply-To: <536110.72154.qm@web26008.mail.ukl.yahoo.com>
References: <536110.72154.qm@web26008.mail.ukl.yahoo.com>
On 03/04/11 10:34, Glyn Astill wrote:
> I'm wondering (and this may be a can of worms) what peoples opinions
are on these schedulers?
When testing our new DB box just last month, we saw a big improvement in
bonnie++ random I/O rates when using the noop scheduler instead of cfq
(or any other). We've got RAID 10/12 on a 3ware card w/ battery-backed
cache; 7200rpm drives. Our file system is XFS with
noatime,nobarrier,logbufs=8,logbsize=256k. How much is "big?" I can't
find my notes for it, but I recall that the difference was large enough
to surprise us. We're running with noop in production right now. No
complaints.
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To: pgsql-performance@postgresql.org
Cc: wayne@databill.com
Subject: Re: Linux I/O schedulers - CFQ & random seeks
In-Reply-To: <4D712978.60504@databill.com>
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