From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60580) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X1ios-0005nb-9n for qemu-devel@nongnu.org; Mon, 30 Jun 2014 17:09:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X1ion-0000yA-Af for qemu-devel@nongnu.org; Mon, 30 Jun 2014 17:08:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61891) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X1ion-0000y2-1d for qemu-devel@nongnu.org; Mon, 30 Jun 2014 17:08:53 -0400 Message-ID: <53B1D1E2.5030105@redhat.com> Date: Mon, 30 Jun 2014 15:08:50 -0600 From: Eric Blake MIME-Version: 1.0 References: In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="drXXN8Ngs8SJk32kbG7Lwme8crlOwAtgt" Subject: Re: [Qemu-devel] Qemu only uses a Qemu File to communicate in two hosts? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gary Jordan , qemu-devel@nongnu.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --drXXN8Ngs8SJk32kbG7Lwme8crlOwAtgt Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 06/30/2014 03:02 PM, Gary Jordan wrote: > Hi, > Does Qemu only use the QEMUFile to load the state of VM after migration= ? Normally, yes. Migration must work as a one-way protocol in the common case when used with default options. There is a migration mode that uses RDMA which requires bi-directional communication in order to speed up aspects of memory migration. But this mode is transparent to the guest, and requires you to take extra steps at both source and destination (along with having an infiniband connection capable of RDMA communication between the two hosts). > Is there a way for two vm guests to communicate like two threads or > processes? If there is, it has nothing to do with migration. It sounds like you are asking about ivshmem and/or virtio; if so, search the archives for recent discussions on the topic. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --drXXN8Ngs8SJk32kbG7Lwme8crlOwAtgt 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 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJTsdHiAAoJEKeha0olJ0NqHd0H/iDMOcR6F9YixAHXRWe8L/ql EYenaUbjiYr0YnHNkneP/XFMx/b3C4MzWib0x/MygM3ewMzo8VJW5DVKaPsn02zd 7Pe5OJnpXcOIiHvn8hSEMnaJ4e0up4PdoLr70LKVIFawrPmst1JQed8Bfo59J6Kw kyR69/RB2JnB0YotjxefSmRdZwgtO3Vd2EfluTB/xH09Q0RbuY0JUXiIpx7QRqBD 6/ekmYK4Yfjtpqzig0X5sjab2NNL0I0izdppu6QrKGLZVaRUA+QiX09OLyQkVZjp ATUTopIc3evE3MUV26hooa9grwC2YwNWzu9SErNk2cN94GRk6pDtBxoTxrMAJjU= =ez5r -----END PGP SIGNATURE----- --drXXN8Ngs8SJk32kbG7Lwme8crlOwAtgt--