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Subject: Re: [tip:tracing/core] ring-buffer benchmark: Run
 producer/consumer threads at nice +19
From: Steven Rostedt <rostedt@goodmis.org>
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Date: Tue, 24 Nov 2009 09:16:47 -0500
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On Mon, 2009-11-23 at 07:15 +0000, tip-bot for Ingo Molnar wrote:
> Commit-ID:  98e4833ba3c314c99dc364012fba6ac894230ad0
> Gitweb:     http://git.kernel.org/tip/98e4833ba3c314c99dc364012fba6ac894230ad0
> Author:     Ingo Molnar <mingo@elte.hu>
> AuthorDate: Mon, 23 Nov 2009 08:03:09 +0100
> Committer:  Ingo Molnar <mingo@elte.hu>
> CommitDate: Mon, 23 Nov 2009 08:03:09 +0100
> 
> ring-buffer benchmark: Run producer/consumer threads at nice +19
> 
> The ring-buffer benchmark threads run on nice 0 by default, using
> up a lot of CPU time and slowing down the system:
> 
>    PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>   1024 root      20   0     0    0    0 D 95.3  0.0   4:01.67 rb_producer
>   1023 root      20   0     0    0    0 R 93.5  0.0   2:54.33 rb_consumer
>  21569 mingo     40   0 14852 1048  772 R  3.6  0.1   0:00.05 top
>      1 root      40   0  4080  928  668 S  0.0  0.0   0:23.98 init
> 
> Renice them to +19 to make them less intrusive.

Ingo, that is the point of a benchmark!

This module is not made to be run all the time. I know you do it for
testing. But running it at lowest priority kills the reason this module
was made in the first place!

-- Steve