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Date: Tue, 24 Nov 2009 16:22:45 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org,
       fweisbec@gmail.com, a.p.zijlstra@chello.nl, efault@gmx.de,
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Subject: Re: [tip:tracing/core] ring-buffer benchmark: Run producer/consumer
 threads at nice +19
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* Steven Rostedt <rostedt@goodmis.org> wrote:

> On Tue, 2009-11-24 at 15:39 +0100, Ingo Molnar wrote:
> 
> > > 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!
> > 
> > Well, it also found quite a few bugs in the ring-buffer code, beyond 
> > benchmarking so i'd like to use it even without looking at the 
> > numbers.
> 
> OK, then lets make a module option (and command line) that will allow 
> the setting of the priority of the threads. Either nice or even fifo 
> (use at your own risk ;-)

Yeah, that's fine to me - as long as the default is unintrusive. (i.e. 
like the rcutorture threads, which run at nice +19 too - and kmemcheck 
which runs at +19 as well.)

We still have the perl overhead in function-tracing kernel builds btw
:-/

	Ingo