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Date: Fri, 27 Aug 2010 15:57:51 -0400
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Steven Rostedt <rostedt@goodmis.org>, Tony Lindgren <tony@atomide.com>,
        Mike Galbraith <efault@gmx.de>
Subject: Re: [RFC PATCH 00/11] sched: CFS low-latency features
Message-ID: <20100827195751.GA1030@Krystal>
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* Peter Zijlstra (peterz@infradead.org) wrote:
> On Fri, 2010-08-27 at 14:32 -0400, Mathieu Desnoyers wrote:
> > 
> > These are problems you get only when you allow spawning any number of threads.
> > If, instead, you create a thread pool at timer creation, then you can allow
> > concurrency without problems with spawner context and error proparation.
> 
> That would be a massive resource waste for the normal case where the
> interval > handler runtime.

Not if the application can configure this value. So the "normal" case could be
set to 1 single thread. Only resource-intensive apps would set this differently,
e.g. to the detected number of cpus.

Mathieu


-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com