Message-ID: <4AA7FB13.9060603@nortel.com>
Date: Wed, 09 Sep 2009 12:59:31 -0600
From: "Chris Friesen" <cfriesen@nortel.com>
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To: Ingo Molnar <mingo@elte.hu>
CC: Theodore Tso <tytso@mit.edu>, mingo@redhat.com, hpa@zytor.com,
       linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, efault@gmx.de,
       tglx@linutronix.de, linux-tip-commits@vger.kernel.org
Subject: Re: [tip:sched/core] sched: Turn off child_runs_first
References: <1252486344.28645.18.camel@marge.simson.net> <tip-2bba22c50b06abe9fd0d23933b1e64d35b419262@git.kernel.org> <20090909175724.GY22901@mit.edu> <20090909180856.GA7323@elte.hu>
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On 09/09/2009 12:08 PM, Ingo Molnar wrote:
> 
> * Theodore Tso <tytso@mit.edu> wrote:

>> Wasn't one of the reasons why we historically did child_runs_first 
>> was so that for fork/exit workloads, the child has a chance to 
>> exec the new process?  If the parent runs first, then more pages 
>> will probably need to be COW'ed.
> 
> That kind of workload should be using vfork() anyway, and be even 
> faster because it can avoid the fork overhead, right?

According to my man page, POSIX.1-2008 removes the specification  of
vfork().

Chris
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