From mboxrd@z Thu Jan  1 00:00:00 1970
From: Robert Hancock <hancockrwd@gmail.com>
Subject: Re: Why is only one command issue per time in AHCI driver?
Date: Tue, 18 Jan 2011 08:43:22 -0600
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On Tue, Jan 18, 2011 at 1:56 AM, Seed <seedrubbish@gmail.com> wrote:
> Hi Robert,
>
> On Fri, Jan 14, 2011 at 4:47 PM, Robert Hancock <hancockrwd@gmail.com> wrote:
>> That sounds like the I/O pattern doesn't result in any concurrent transfers
>> being executed. What kind of workload is this running?
>>
>
> Do you have any suggestion about how to can get such a workload?

It depends very much on what you're trying to accomplish. Last time I
checked, even booting the system or doing large sequential I/O would
result in fairly high queue depths. However if you're doing small,
single-threaded I/O, you likely won't see much or any queueing.