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Date: Fri, 1 Oct 2010 17:27:19 +0200
From: Frederic Weisbecker <fweisbec@gmail.com>
To: "Van De Ven, Arjan" <arjan.van.de.ven@intel.com>
Cc: Christoph Lameter <cl@linux.com>, Pekka Enberg <penberg@cs.helsinki.fi>,
        "Wu, Xia" <xia.wu@intel.com>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "viro@zeniv.linux.org.uk" <viro@zeniv.linux.org.uk>,
        "mingo@elte.hu" <mingo@elte.hu>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Zhu, Daniel" <daniel.zhu@intel.com>,
        "Wang, Yong Y" <yong.y.wang@intel.com>
Subject: Re: unnecessary timer interrupt of slab.c and bdi tasks when the
	system is in sleep state
Message-ID: <20101001152715.GA5338@nowhere>
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On Fri, Oct 01, 2010 at 08:20:22AM -0700, Van De Ven, Arjan wrote:
> 
> > > the slab timer is already deferable... which means it won't hit while
> > the system is completely idle.
> > 
> > 
> > I'm not sure what you mean exactly. The slab work seems to be scheduled
> > strictly
> > periodically, unless the cpu goes offline. But I can't find any nohz-
> > wise adaptation.
> > 
> 
>                 INIT_DELAYED_WORK_DEFERRABLE(reap_work, cache_reap);
> 
> that will cause it to only run when the cpu is actually idle...


Aah ok, I missed that. Thanks.