public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: Tomasz Chmielewski <mangoo@wpkg.org>
To: kvm@vger.kernel.org
Subject: Houston, we have May 15, 1953 (says guest when host uses cpufreq, and dies)
Date: Wed, 18 Feb 2009 15:51:22 +0100	[thread overview]
Message-ID: <499C206A.5050109@wpkg.org> (raw)

Is using cpufreq (i.e. with ondemand governor) on KVM host safe for guests?

I enabled cpufreq on the host, it scaled down the host CPU (Dual-Core 
AMD Opteron(tm) Processor 2212) to 1 GHz from 2 GHz.

Guest (using 1 CPU) was still showing that it has a 2 GHz CPU in 
/proc/cpuinfo (I guess this value is read only once, when booting).

After about 2 hours I started "date" on the guest - it showed that it's 
year *1953*, after which I couldn't start any other command (the guest 
was technically alive - SSH connection to it didn't die - but I couldn't 
do anything).

# date
Wed Feb 18 13:07:17 CET 2009

[let's wait ~2 hours]


# date
Fri May 15 10:13:14 CET 1953
# date
^C^Z
[could not interrupt]


Is it expected behaviour? Is it correct behaviour?


-- 
Tomasz Chmielewski
http://wpkg.org

             reply	other threads:[~2009-02-18 14:51 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-18 14:51 Tomasz Chmielewski [this message]
2009-02-18 16:02 ` Houston, we have May 15, 1953 (says guest when host uses cpufreq, and dies) Anthony Liguori
2009-02-18 16:11   ` Tomasz Chmielewski
2009-02-18 16:59     ` Avi Kivity
2009-02-18 17:02       ` Tomasz Chmielewski
2009-02-18 20:37       ` Anthony Liguori
2009-02-19  9:15         ` Gerd Hoffmann
2009-02-19  9:20           ` Tomasz Chmielewski
2009-02-19 10:27             ` Gerd Hoffmann
2009-02-18 18:46 ` Marcelo Tosatti
2009-02-18 18:53   ` Tomasz Chmielewski
2009-02-18 18:57     ` Marcelo Tosatti
2009-02-18 19:07       ` Tomasz Chmielewski
2009-02-18 19:10         ` Marcelo Tosatti
2009-02-18 19:18           ` Tomasz Chmielewski
2009-02-18 19:32             ` Marcelo Tosatti
2009-02-18 20:02               ` Tomasz Chmielewski
2009-02-18 20:03                 ` Marcelo Tosatti
2009-02-19 14:43                   ` Tomasz Chmielewski
2009-03-07 14:59       ` Tomasz Chmielewski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=499C206A.5050109@wpkg.org \
    --to=mangoo@wpkg.org \
    --cc=kvm@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox