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From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: Bas van der Oest <bassvdo@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: /proc/stat information incorrect
Date: Fri, 20 Apr 2012 14:06:54 +0200	[thread overview]
Message-ID: <20120420140654.793a40f2@de.ibm.com> (raw)
In-Reply-To: <CABWpNyaw3Xq7FJ4A0itYEFLN1QdwBvvqs0rVxB1z-cyaUcmuVw@mail.gmail.com>

On Tue, 17 Apr 2012 10:04:35 +0200
Bas van der Oest <bassvdo@gmail.com> wrote:

> > Assuming that you are on a recent kernel (>= 3.2), could you please
> > try to revoke git commit a25cac5198d4ff28 "proc: Consider NO_HZ when
> > printing idle and iowait times" and try again ?
> 
> I revoked the patch and this certainly had effect, however I still
> doubt if the result is completely correct now.
> It now seems that CPU4 (this one is handling the irqs now) spends more
> time than the other CPUs:
> 
>         user    nice    system  idle    iowait  irq   softirq sum
> cpu     4       0       412     8186    0       0       79      8681
> cpu0    0       0       1       1074    0       0       1       1076
> cpu1    0       0       2       1075    0       0       0       1077
> cpu2    0       0       1       1075    0       0       0       1076
> cpu3    0       0       1       1079    0       0       0       1080
> cpu4    1       0       115     941     0       0       78      1135
> cpu5    2       0       99      984     0       0       0       1085
> cpu6    0       0       98      977     0       0       0       1075
> cpu7    0       0       95      980     0       0       0       1075
> 
> Any suggestions where this small difference is coming from?

CONFIG_IRQ_TIME_ACCOUNTING comes to mind. Is this enabled for your
kernel ?

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.


  reply	other threads:[~2012-04-20 12:07 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-16  8:04 /proc/stat information incorrect Bas van der Oest
2012-04-16 12:36 ` Martin Schwidefsky
2012-04-17  8:04   ` Bas van der Oest
2012-04-20 12:06     ` Martin Schwidefsky [this message]
2012-04-25  7:24       ` Bas van der Oest

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