From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Bastian Blank <waldi@debian.org>, xen-devel@lists.xensource.com
Subject: Re: 25% cpu usage during idle
Date: Wed, 22 Sep 2010 17:12:14 -0700 [thread overview]
Message-ID: <4C9A9B5E.50408@goop.org> (raw)
In-Reply-To: <20100728192608.GB21304@wavehammer.waldi.eu.org>
On 07/28/2010 12:26 PM, Bastian Blank wrote:
> A new pvops kernel (78b55f90e72348e231092dbe3e50ac7414b9e1af) needs around 25%
> cpu while being idle with 32 guest domains in event and ksoftirq kernel
> threads:
I've never seen it that high, but it looks like something in the pty
layer will spin waking up at HZ rate if you have buffered console output
pending. If you do x[lm] console for each domain you can quieten it
down. Does that match what you're seeing?
You can also see it with powertop.
J
> | root 4 3.6 0.0 0 0 ? S 21:08 0:26 [ksoftirqd/0]
> | root 7 8.6 0.0 0 0 ? S 21:08 1:03 [ksoftirqd/1]
> | root 10 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/2]
> | root 13 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/3]
> | root 16 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/4]
> | root 19 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/5]
> | root 22 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/6]
> | root 25 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/7]
> | root 28 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/8]
> | root 31 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/9]
> | root 34 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/10]
> | root 37 0.0 0.0 0 0 ? S 21:08 0:00 [ksoftirqd/11]
> | root 39 1.3 0.0 0 0 ? S 21:08 0:09 [events/0]
> | root 40 14.0 0.0 0 0 ? S 21:08 1:44 [events/1]
> | root 41 0.0 0.0 0 0 ? S 21:08 0:00 [events/2]
> | root 42 0.0 0.0 0 0 ? S 21:08 0:00 [events/3]
> | root 43 0.1 0.0 0 0 ? S 21:08 0:00 [events/4]
> | root 44 0.0 0.0 0 0 ? S 21:08 0:00 [events/5]
> | root 45 0.0 0.0 0 0 ? S 21:08 0:00 [events/6]
> | root 46 0.0 0.0 0 0 ? S 21:08 0:00 [events/7]
> | root 47 0.0 0.0 0 0 ? S 21:08 0:00 [events/8]
> | root 48 0.0 0.0 0 0 ? S 21:08 0:00 [events/9]
> | root 49 0.0 0.0 0 0 ? S 21:08 0:00 [events/10]
> | root 50 0.0 0.0 0 0 ? S 21:08 0:00 [events/11]
>
> Bastian
>
prev parent reply other threads:[~2010-09-23 0:12 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-28 19:26 25% cpu usage during idle Bastian Blank
2010-07-28 19:34 ` Jeremy Fitzhardinge
2010-09-23 0:12 ` Jeremy Fitzhardinge [this message]
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