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Date: Mon, 12 Mar 2007 15:22:16 +0100
From: Andi Kleen <andi@firstfloor.org>
To: Theodore Tso <tytso@mit.edu>, Andi Kleen <andi@firstfloor.org>,
       Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
       Roland McGrath <roland@redhat.com>, akpm@linux-foundation.org,
       mm-commits@vger.kernel.org, npiggin@suse.de, drepper@redhat.com,
       oleg@tv-sign.ru, sebastien.dugue@bull.net, linux-kernel@vger.kernel.org
Subject: Re: [patch] change futex_wait() to hrtimers
Message-ID: <20070312142216.GA15357@one.firstfloor.org>
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> This becomes especially important if we want the tickless code to
> really shine as far as power management is concerned.  Unfortunately,
> the POSIX timer abstraction doesn't give this kind of flexibility
> easily, so it's going to be a while before we see significant
> userspace adoption of such a kernel feature, but I think it's
> something that would be still worthwhile to add.

I suspect it would be overkill to specify that on every sleep operation.
99% of applications won't care and for the 1% leftover a global per 
process setting should be fine.
I think a single prctl() and a global sysctl as default would be enough.

-Andi