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From: Gregory Haskins <gregory.haskins@gmail.com>
To: emilne@redhat.com
Cc: linux-scsi@vger.kernel.org
Subject: Re: Slow writes to SAS drives on LSI mpt2sas HBA
Date: Thu, 6 Dec 2012 20:43:38 -0500	[thread overview]
Message-ID: <450090F8-2B0F-4B38-AB7C-2154C75043F9@gmail.com> (raw)
In-Reply-To: <1354572400.4420.66.camel@localhost.localdomain>

Hello Ewan

On Dec 3, 2012, at 5:06 PM, Ewan Milne <emilne@redhat.com> wrote:

>> 
> 
> It sounds like your drive write cache is disabled, 7200RPM is 120
> revolutions/sec, and you are getting 7747584 / 1024 / 63.59 = ~119 IO/s
> I believe the write cache is enabled by default on SATA drives, which
> would explain the difference.

You were exactly right.  Thank you!

A quick "sdparm -S -set=WCE <dev>" and I was back to where I expected.

Thanks again,
-Greg

      reply	other threads:[~2012-12-07  1:43 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-03 19:48 Slow writes to SAS drives on LSI mpt2sas HBA Gregory Haskins
2012-12-03 22:06 ` Ewan Milne
2012-12-07  1:43   ` Gregory Haskins [this message]

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