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Message-ID: <1322558612.2921.182.camel@twins>
Subject: Re: [PATCH 0/4] delayacct: save max CPU/IO/SWAP/RECLAIM delays
From: Peter Zijlstra <peterz@infradead.org>
To: Satoru Moriya <satoru.moriya@hds.com>
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        "dle-develop@lists.sourceforge.net" 
	<dle-develop@lists.sourceforge.net>,
        Seiji Aguchi <seiji.aguchi@hds.com>
Date: Tue, 29 Nov 2011 10:23:32 +0100
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On Mon, 2011-11-28 at 17:44 -0500, Satoru Moriya wrote:
> In the latency sensitive systems, we usually focus on the worst latency.
> And so, it is useful to save max delays into the per-task delay
> accounting functionality.
> 
> Example output:
> (on 100 concurrent dd reading sparse files w/ 1 dd writing a file)
> 
> CPU             count     real total  virtual total    delay total      delay_max  delay average
>                   222       45993008       74603882        7637295        3691858          0.034ms
> IO              count    delay total      delay max  delay average
>                     2       21812073       12728672             10ms
> SWAP            count    delay total      delay max  delay average
>                     0              0              0              0ms
> RECLAIM         count    delay total      delay_max  delay average
>                     2         348488         211985              0ms
> 
> Any comments are welcome.

No!!!

Linus told us to be bastards, so there you have it.

There's way too many different accounting crap thingies around. And now
I get a patch without any justification what so ever. So no, piss off.