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Date: Thu, 20 Aug 2009 17:16:03 +0530
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Subject: Re: [tip:sched/core] sched: cpuacct: Use bigger percpu counter batch 
	values for stats counters
From: Balbir Singh <balbir@linux.vnet.ibm.com>
To: Anton Blanchard <anton@samba.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Bharata B Rao <bharata@linux.vnet.ibm.com>,
       KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
       Ingo Molnar <mingo@elte.hu>, mingo@redhat.com, hpa@zytor.com,
       linux-kernel@vger.kernel.org, schwidefsky@de.ibm.com,
       balajirrao@gmail.com, dhaval@linux.vnet.ibm.com, tglx@linutronix.de,
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Hi, Anton,

Do you have any data on what level of batching is good for
VIRT_CPU_ACCOUNTING? If it is going to be as high as INT_MAX, then
your patch seems to be the best way to go forward. We'll need to herd
away bad users who read cpuacct.stat frequently enough to create a
problem.

Balbir Singh.