From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:33419) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TC9FS-0004Yn-AK for qemu-devel@nongnu.org; Thu, 13 Sep 2012 09:14:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TC9FL-0007R9-1E for qemu-devel@nongnu.org; Thu, 13 Sep 2012 09:14:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44323) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TC9FK-0007Qs-PE for qemu-devel@nongnu.org; Thu, 13 Sep 2012 09:14:18 -0400 Message-ID: <5051DC20.4090204@redhat.com> Date: Thu, 13 Sep 2012 07:14:08 -0600 From: Eric Blake MIME-Version: 1.0 References: <87pq5r5otp.fsf@codemonkey.ws> <20120912151549.GT20907@redhat.com> <87y5kfrtne.fsf@codemonkey.ws> <20120913104940.GA20907@redhat.com> In-Reply-To: <20120913104940.GA20907@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enig343EF726D4FF6F5D7548DF8D" Subject: Re: [Qemu-devel] Rethinking missed tick catchup List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gleb Natapov Cc: qemu-devel@nongnu.org, Jan Kiszka , Michael Roth , Luiz Capitulino , Avi Kivity , Anthony Liguori , Paolo Bonzini This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig343EF726D4FF6F5D7548DF8D Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 09/13/2012 04:49 AM, Gleb Natapov wrote: >> They do if you hibernate your laptop. >> > AFAIK libvirt migrates vm into a file on hibernate. It is better to mov= e to S3 > (using qemu-ga) instead and migrate to file only if s3 fails. On host hibernate, libvirt currently does nothing to the guest. When the host resumes, the guests see a large gap in execution. Libvirt would need a hook into host hibernation, to have enough time to tell the guests to go into S3 prior to allowing the host to go into S3. On host reboot, libvirt currently saves guests to disk using migrate to file. The ideal solution would be to first tell the guest to go into S3 before migrating to file, but the migration to file STILL must occur, because the host is about to reboot and S3 is not persistent. S3 is a better solution than S4, in that S4 requires the guest to have enough memory (and if it doesn't cooperate, data is lost), but with S3, even if the guest doesn't cooperate, we can still fall back to migration to file with the guest only losing time, but not data. --=20 Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --------------enig343EF726D4FF6F5D7548DF8D Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iQEcBAEBCAAGBQJQUdwhAAoJEKeha0olJ0NqxR8H/R7/8XKzTP41AO77o1xKlEg8 QdNNtV6eoN+pSZvbIlIKj5Dsk7mfQ+QCxQ+zKigE+uyFL1a5HfveZiHIkJeFabiA 7TFeh/Uutkk0h0EpAai2xXWXKJMbBUvTRuiQsCG6weIs/bPzx2yLyXDgYm4BxhnB y9gPdhDpIhVFoFKoc08ANuMqP8KuIQHj0J+A4h7XSw7NnWUGy7T+wfhOFn9XJgqM K0iPvZaWbfBxghpYwFMU11ElSbR+29vfwteRe/SYMQA8gXt7Pw4pY2ta4q7zp8W3 2J8+kwYHcFYn2Fv+iIqlSdJA3s/6VlZkVi9yhVe2+3du5NXyhVWBCkZ9ww9Cscw= =9PLn -----END PGP SIGNATURE----- --------------enig343EF726D4FF6F5D7548DF8D--