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Date: Tue, 4 Jul 2006 09:32:49 +0800
From: Fengguang Wu <wfg@mail.ustc.edu.cn>
To: Jens Axboe <axboe@suse.de>
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@osdl.org>,
       Nick Piggin <nickpiggin@yahoo.com.au>, Lubos Lunak <l.lunak@suse.cz>
Subject: Re: [PATCH 7/7] iosched: introduce deadline_kick_page()
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Jens,

On Wed, Jun 28, 2006 at 01:27:32PM +0200, Jens Axboe wrote:
> > The overhead of deadline_kick_page() becomes large when the request is
> > large (256 pages). But I guess there's way to optimize it:
> > - most requests will be consisted of a set of continuous pages, i.e. a
> >   range comparison will be sufficient.
> > - for a system with lots of queued requests(>100), maybe the gain can
> >   well pay for the overheads?
> 
> Sorry, there's just no way that something like that is acceptable for
> inclusion. I don't care much about the overhead numbers (I can see from
> the code that it sucks :-), I wanted to see some numbers on what
> scenarios this helps performance and by how much.

Ok, thanks. I hope that I'll be able to bring with some performance
numbers the next time :-)

Regards,
Wu