All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stefan Hajnoczi <stefanha@gmail.com>
To: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
Cc: Orit Wasserman <owasserm@redhat.com>, Peter Lieven <pl@kamp.de>,
	qemu-devel <qemu-devel@nongnu.org>,
	Dave Gilbert <dgilbert@redhat.com>,
	Juan Quintela <quintela@redhat.com>
Subject: Re: [Qemu-devel] memory allocation of migration changed?
Date: Tue, 11 Feb 2014 16:44:49 +0100	[thread overview]
Message-ID: <CAJSP0QWyA195Pdhy_juSimfnuPFTakwcHtN2beyJdE31ghgemQ@mail.gmail.com> (raw)
In-Reply-To: <52FA399F.6070802@profihost.ag>

On Tue, Feb 11, 2014 at 3:54 PM, Stefan Priebe - Profihost AG
<s.priebe@profihost.ag> wrote:
> in the past (Qemu 1.5) a migration failed if there was not enogh memory
> on the target host available directly at the beginning.
>
> Now with Qemu 1.7 i've seen succeeded migrations but the kernel OOM
> memory killer killing qemu processes. So the migration seems to takes
> place without having anough memory on the target machine?

How much memory is the guest configured with?  How much memory does
the host have?

I wonder if there are zero pages that can be migrated almost "for
free" and the destination host doesn't touch.  When they are touched
for the first time after migration handover, they need to be allocated
on the destination host.  This can lead to OOM if you overcommitted
memory.

Can you reproduce the OOM reliably?  It should be possible to debug it
and figure out whether it's just bad luck or a true regression.

Stefan

  reply	other threads:[~2014-02-11 15:45 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-02-11 14:54 [Qemu-devel] memory allocation of migration changed? Stefan Priebe - Profihost AG
2014-02-11 15:44 ` Stefan Hajnoczi [this message]
2014-02-11 16:22   ` Peter Lieven
2014-02-11 18:32     ` Stefan Priebe
2014-02-14 14:59       ` Stefan Hajnoczi
2014-02-14 18:15         ` Stefan Priebe
2014-02-11 18:30   ` Stefan Priebe
2014-02-14 15:03     ` Stefan Hajnoczi
2014-02-14 18:16       ` Stefan Priebe
2014-02-24 15:00         ` Stefan Hajnoczi
2014-02-24 16:13           ` Eric Blake
2014-03-12 19:15             ` Stefan Priebe

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=CAJSP0QWyA195Pdhy_juSimfnuPFTakwcHtN2beyJdE31ghgemQ@mail.gmail.com \
    --to=stefanha@gmail.com \
    --cc=dgilbert@redhat.com \
    --cc=owasserm@redhat.com \
    --cc=pl@kamp.de \
    --cc=qemu-devel@nongnu.org \
    --cc=quintela@redhat.com \
    --cc=s.priebe@profihost.ag \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.