Subject: Re: [RFC/RFT PATCH v3] sched: automated per tty task groups
From: Mike Galbraith <efault@gmx.de>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>,
        Hans-Peter Jansen <hpj@urpla.net>, linux-kernel@vger.kernel.org,
        Lennart Poettering <mzxreary@0pointer.de>,
        Linus Torvalds <torvalds@linux-foundation.org>, david@lang.hm,
        Dhaval Giani <dhaval.giani@gmail.com>, Vivek Goyal <vgoyal@redhat.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Markus Trippelsdorf <markus@trippelsdorf.de>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Ingo Molnar <mingo@elte.hu>, Balbir Singh <balbir@linux.vnet.ibm.com>
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Date: Fri, 19 Nov 2010 05:38:56 -0700
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On Fri, 2010-11-19 at 12:49 +0100, Peter Zijlstra wrote:

> You add a lot of pointer chasing to all the scheduler fast paths and
> there is quite significant data size bloat for even compiling with the
> controller enabled, let alone actually using the stuff.

The pointer chasing hurts, but fast path + global spinlock is what
slapped the hierarchical outta me :)

	-Mike

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