From: kenneth johansson <ken@kenjo.org>
To: Tejun Heo <htejun@gmail.com>
Cc: linux-ide@vger.kernel.org
Subject: Re: ahci problems with sata disk.
Date: Tue, 16 Jan 2007 02:43:47 +0100 [thread overview]
Message-ID: <1168911827.7718.4.camel@duo> (raw)
In-Reply-To: <45AB86C0.2020507@gmail.com>
On Mon, 2007-01-15 at 22:50 +0900, Tejun Heo wrote:
> kenneth johansson wrote:
> > On Mon, 2007-01-15 at 18:13 +0900, Tejun Heo wrote:
> >> kenneth johansson wrote:
> >>> I changed my bios setting for SATA from IDE to AHCI.
> >>>
> >>> This resulted in some "interesting" read throughput.
> >>>
> >>> plots can be found at http://kenjo.org/~ken/sata/
> >>> The plots was done on a live disk so some noise is expected but in the
> >>> ahci mode the throughput get stuck at 17 MB way to much.
> >> It's probably not an ahci problem but more of NCQ implementation problem
> >> in the drive firmware. Please report the result of 'hdparm -I /dev/sdX'
> >> and try adjust queue depth and see what happens.
> >>
> >> http://linux-ata.org/faq.html
> >>
> >
> > It was, when I turn of NCQ with "echo 1
> >> /sys/block/sda/device/queue_depth" I get the same performance as when
> > the BIOS is set to IDE.
>
> Can you play with queue depth a bit? e.g. Benchmark queue depth of 4, 8
> and 16.
I did some more test "http://kenjo.org/~ken/sata/" and queue 1 and maybe
2 works but everything larger than that has problems.
next prev parent reply other threads:[~2007-01-16 1:43 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-01-14 14:32 ahci problems with sata disk kenneth johansson
2007-01-15 9:13 ` Tejun Heo
2007-01-15 11:05 ` kenneth johansson
2007-01-15 11:36 ` Alan
2007-01-15 13:50 ` Tejun Heo
2007-01-16 1:43 ` kenneth johansson [this message]
2007-01-16 16:44 ` Andrew Lyon
2007-01-16 18:32 ` Mark Lord
2007-01-16 20:20 ` Mark Hahn
2007-01-16 22:10 ` Jeff Garzik
2007-01-16 22:26 ` Eric D. Mudama
2007-01-17 22:03 ` Jens Axboe
2007-01-17 22:03 ` Jens Axboe
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