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Subject: Re: [RFC patch 1/2] sched: dynamically adapt granularity with
 nr_running
From: Steven Rostedt <rostedt@goodmis.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
        Thomas Gleixner <tglx@linutronix.de>, Tony Lindgren <tony@atomide.com>
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Date: Mon, 13 Sep 2010 09:52:47 -0400
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On Mon, 2010-09-13 at 10:41 +0200, Peter Zijlstra wrote:

> Yeah, without it you can starve the already running task on massive
> forks.
> 
> Still, I'm not quite sure why people really care about fork() on time
> sensitive paths, its a very expensive thing to do, pre-fork() and wake
> when you need it, is what I would say.

Fork is used all over the place in Linux. Every shell script uses it to
execute commands. Bad fork behavior shows up in just doing a build of
the kernel.

-- Steve