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Date: Thu, 28 Nov 2013 15:59:48 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Tejun Heo <htejun@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>, zhang.yi20@zte.com.cn,
        lkml <linux-kernel@vger.kernel.org>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH]: exec: avoid propagating PF_NO_SETAFFINITY into
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On Thu, Nov 28, 2013 at 09:57:23AM -0500, Tejun Heo wrote:
> On Thu, Nov 28, 2013 at 03:55:05PM +0100, Peter Zijlstra wrote:
> > Because that is exactly what some users desire? Some RT and HPC people
> > want all those crypt jobs to run on a few designated cpus and not wreck
> > their compute jobs.
> 
> And you can't do that reliably from userland.  Those things are
> created dynamically.  workqueue provides per-workqueue attributes to
> enable those use cases.  It doesn't have system-wide default
> attributes right now but adding that shouldn't be too difficult.

Like a parent process, right? So people can use the existing task
interfaces.

Or are we going to tell people; here, there's cgroups for managing your
tasks. Oh and here is this crippled interface X for if you want to
manage these few tasks, and interface Y for managing these other few
tasks.