Date: Fri, 1 Dec 2006 18:27:49 +0100
From: Jens Axboe <jens.axboe@oracle.com>
To: "Raz Ben-Jehuda(caro)" <raziebe@gmail.com>
Cc: linux-aio@kvack.org, Linux Kernel <linux-kernel@vger.kernel.org>,
       suparna@in.ibm.com
Subject: Re: slow io_submit
Message-ID: <20061201172749.GZ5400@kernel.dk>
References: <5d96567b0612010904s361b799t8db72accc287ca54@mail.gmail.com>
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On Fri, Dec 01 2006, Raz Ben-Jehuda(caro) wrote:
> Jens suparna hello
> 
> I have managed to understand why io_submit is sometimes very slow.
> It is because the device is plugged once too many io's are being sent.
> I have conducted a simple test with nr_request to default value of 128
> and and 256.
> and it proved to be correct.

I don't understand your email. The device is plugged when it is empty,
not when it has emptied the request list.

> I would truely appreciate your comment on this.

On what? :-)

If it's no blocking and returning EAGAIN instead, then I agree this is
what should eventually happen. Right now nobody is working on that
afaik, so it's not something that will hit the next kernel.

-- 
Jens Axboe

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