From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Bart Van Assche" <bart.vanassche@gmail.com>
Subject: Re: Intel X25-M MLC SSD benchmarks
Date: Fri, 12 Dec 2008 08:15:01 +0100
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To: "Eric D. Mudama" <edmudama@gmail.com>
Cc: Raz Ben-Yehuda <razb@bitband.com>, Matthew Wilcox <matthew@wil.cx>, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org

On Fri, Dec 12, 2008 at 5:55 AM, Eric D. Mudama <edmudama@gmail.com> wrote:
> On 12/11/08, Eric D. Mudama <edmudama@gmail.com> wrote:
>> Out of curiosity, is write cache enabled or disabled on these devices?
>
> Oops, I just noticed the oflag=direct, that can have a huge
> performance difference depending on the block size.
>
> What numbers are you getting without oflag=direct?

IMHO repeating the measurements without oflag=direct does not make
sense: measurements with oflag=direct tell something about the
performance of the SSD and the software layers on top of it. Without
oflag=direct writes are buffered by Linux and data is written
asynchronously to the SSD.

Bart.