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Date: Wed, 12 Nov 2008 12:35:14 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Linux Kernel <linux-kernel@vger.kernel.org>,
       Dhaval Giani <dhaval@linux.vnet.ibm.com>,
       Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
       Vaidyanathan S <svaidyan@in.ibm.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Bharata B Rao <bharata@linux.vnet.ibm.com>
Subject: Re: [PATCH][mmotm] Sched fix stale value in average load per task
Message-ID: <20081112113514.GB6372@elte.hu>
References: <20081112104900.GA13896@balbir.in.ibm.com>
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* Balbir Singh <balbir@linux.vnet.ibm.com> wrote:

> cpu_avg_load_per_task() returns a stale value when nr_running is 0. 
> It returns an older stale (caculated when nr_running was non zero) 
> value. This patch returns and sets rq->avg_load_per_task to zero 
> when nr_running is 0.
> 
> Compile and boot tested on a x86_64 box.
> 
> Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
> ---
> 
>  kernel/sched.c |    2 ++
>  1 file changed, 2 insertions(+)

applied to tip/sched/urgent, thanks Balbir!

i'm wondering, have you observed load-balancer misbehavior due to this 
load-average imprecision bug, on some workload? (or have you found 
this via code review)

	Ingo