From: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
To: Corrado Zoccolo <czoccolo@gmail.com>
Cc: jens.axboe@oracle.com, Linux-Kernel <linux-kernel@vger.kernel.org>
Subject: Re: Reduce latencies for syncronous writes and high I/O priority requests in deadline IO scheduler
Date: Thu, 23 Apr 2009 11:18:27 +0000 [thread overview]
Message-ID: <4d8e3fd30904230418g20e89cb1se4303754914bbcd7@mail.gmail.com> (raw)
In-Reply-To: <4e5e476b0904221407v7f43c058l8fc61198a2e4bb6e@mail.gmail.com>
On 4/22/09, Corrado Zoccolo <czoccolo@gmail.com> wrote:
> Hi,
> deadline I/O scheduler currently classifies all I/O requests in only 2
> classes, reads (always considered high priority) and writes (always
> lower).
> The attached patch, intended to reduce latencies for syncronous writes
> and high I/O priority requests, introduces more levels of priorities:
> * real time reads: highest priority and shortest deadline, can starve
> other levels
> * syncronous operations (either best effort reads or RT/BE writes),
> mid priority, starvation for lower level is prevented as usual
> * asyncronous operations (async writes and all IDLE class requests),
> lowest priority and longest deadline
>
numbers are impressive.
do you observe better latencies in normal desktop usage as well?
ciao,
--
Paolo
http://paolo.ciarrocchi.googlepages.com/
http://mypage.vodafone.it/
next prev parent reply other threads:[~2009-04-23 11:18 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-22 21:07 Corrado Zoccolo
2009-04-23 11:18 ` Paolo Ciarrocchi [this message]
2009-04-23 11:28 ` Jens Axboe
2009-04-23 15:57 ` Corrado Zoccolo
2009-04-23 11:52 ` Aaron Carroll
2009-04-23 12:13 ` Jens Axboe
2009-04-23 16:10 ` Corrado Zoccolo
2009-04-23 23:30 ` Aaron Carroll
2009-04-24 6:13 ` Corrado Zoccolo
2009-04-24 6:39 ` Jens Axboe
2009-04-24 16:07 ` Corrado Zoccolo
2009-04-24 21:37 ` Corrado Zoccolo
2009-04-26 12:43 ` Corrado Zoccolo
2009-05-01 19:30 ` Corrado Zoccolo
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