Message-ID: <1378795659.6046.41.camel@marge.simpson.net>
Subject: Re: [RFC] Restrict kernel spawning of threads to a specified set of
 cpus.
From: Mike Galbraith <bitbucket@online.de>
To: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Christoph Lameter <cl@linux.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Mike Frysinger <vapier@gentoo.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Date: Tue, 10 Sep 2013 08:47:39 +0200
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	 <CAOtvUMe=jcAHXNJU_rTAAokaE4KZNUTFsHVVTTxgFW_xj8ONxg@mail.gmail.com>
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On Tue, 2013-09-10 at 09:05 +0300, Gilad Ben-Yossef wrote: 
> Hi,
> 
> On Thu, Sep 5, 2013 at 11:07 PM, Christoph Lameter <cl@linux.com> wrote:
> > I am not sure how to call this kernel option but we need something like
> > that. I see drivers and the kernel spawning processes on the nohz cores.
> > The name kthread is not really catching the purpose.
> >
> > os_cpus=? highlatency_cpus=?
> >
> 
> First off, thank you for doing this. It is very useful :-)
> 
> Currently if one wishes to run a single task on an isolated CPU with
> as little interference as possible, one needs to pass
> rcu_nocbs, isolcpus, nohz_full parameters and now kthread parameter,
> all pretty much with the same values
> 
> I know some people won't like this, but can we perhaps fold all these
> into a single parameter, perhaps even the existing isolcpus?

isolcpus is supposed to go away, as cpusets can isolate CPUs, and can
turn off load balancing.

-Mike

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