Date: Sun, 28 Mar 2004 19:31:27 +0200
From: Jens Axboe <axboe@suse.de>
To: Jeff Garzik <jgarzik@pobox.com>
Cc: Andrew Morton <akpm@osdl.org>, nickpiggin@yahoo.com.au,
       linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] speed up SATA
Message-ID: <20040328173126.GH24370@suse.de>
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On Sun, Mar 28 2004, Jeff Garzik wrote:
> Jens Axboe wrote:
> >On Sat, Mar 27 2004, Jeff Garzik wrote:
> >
> >>"IOPs" are what make a lot of storage peeps excited these days, so they 
> >>are being pushed in a low-latency direction anyway.
> >
> >
> >IOPS says nothing about latency, it's still 100% throughput oriented.
> 
> 
> In order to achieve a large IOPs number, one must sent a ton of small 
> requests.  Per-request latency as well as overall throughput is a factor.

I don't see how per-request latency is a factor at all, if your metric
is simply iops/sec. You could infinitely starve lots of requests
without hurting your io rate, nor throughput.

-- 
Jens Axboe

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