From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60896) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eMG7p-00083x-Ax for qemu-devel@nongnu.org; Tue, 05 Dec 2017 11:31:18 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eMG7k-000792-GB for qemu-devel@nongnu.org; Tue, 05 Dec 2017 11:31:17 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36996) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eMG7k-00078l-7R for qemu-devel@nongnu.org; Tue, 05 Dec 2017 11:31:12 -0500 Date: Tue, 5 Dec 2017 16:31:09 +0000 From: Stefan Hajnoczi Message-ID: <20171205163109.GC6712@stefanha-x1.localdomain> References: <20171205063313.GB4102@yangzhon-Virtual> <20171205120623.GB31150@stefanha-x1.localdomain> <5f9f2835-5811-3ee0-9049-0d2cddc08958@redhat.com> <876e5376-d729-72d7-3c04-3c6f52b745de@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="z4+8/lEcDcG5Ke9S" Content-Disposition: inline In-Reply-To: <876e5376-d729-72d7-3c04-3c6f52b745de@redhat.com> Subject: Re: [Qemu-devel] About the light VM solution! List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Stefan Hajnoczi , Yang Zhong , qemu-devel --z4+8/lEcDcG5Ke9S Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Dec 05, 2017 at 03:00:10PM +0100, Paolo Bonzini wrote: > On 05/12/2017 14:47, Stefan Hajnoczi wrote: > > On Tue, Dec 5, 2017 at 1:35 PM, Paolo Bonzini wro= te: > >> On 05/12/2017 13:06, Stefan Hajnoczi wrote: > >>> On Tue, Dec 05, 2017 at 02:33:13PM +0800, Yang Zhong wrote: > >>>> As you know, AWS has decided to switch to KVM in their clouds. This = news make almost all > >>>> china CSPs(clouds service provider) pay more attention on KVM/Qemu, = especially light VM > >>>> solution. > >>>> > >>>> Below are intel solution for light VM, qemu-lite. > >>>> http://events.linuxfoundation.org/sites/events/files/slides/Light%20= weight%20virtualization%20with%20QEMU%26KVM_0.pdf > >>>> > >>>> My question is whether community has some plan to implement light VM= or alternative solutions? If no, whether our > >>>> qemu-lite solution is suitable for upstream again? Many thanks! > >>> > >>> What caused a lot of discussion and held back progress was the approa= ch > >>> that was taken. The basic philosophy seems to be bypassing or > >>> special-casing components in order to avoid slow operations. This > >>> requires special QEMU, firmware, and/or guest kernel binaries and cau= ses > >>> extra work for the management stack, distributions, and testers. > >> > >> I think having a special firmware (be it qboot or a special-purpose > >> SeaBIOS) is acceptable. > >=20 > > The work Marc Mari Barcelo did in 2015 showed that SeaBIOS can boot > > guests quickly. The guest kernel was entered in <35 milliseconds > > IIRC. Why is special firmware necessary? >=20 > I thought that wasn't the "conventional" SeaBIOS, but rather one with > reduced configuration options, but I may be remembering wrong. Marc didn't spend much time on optimizing SeaBIOS, he used the build options that were suggested. An extra flag can be added in qemu_preinit() to skip slow init that's unnecessary on optimized machines. That would allow a single SeaBIOS binary to run both full and lite systems. Stefan --z4+8/lEcDcG5Ke9S Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJaJsnNAAoJEJykq7OBq3PI5QIH/315micZ0b9vrbuBdNYnYM/U jBu6t8BCd+1RUlT+Zib0z5rdPJFY8xKaebUTabOd4plFUGzLOlZbgdv/jvaOUY5t x9BbsmEiw5MSfi5PMIBZM+aucRNIbw+LHftRQKVG0+6r30QhQDVtRuU7cPMHz0se Z79tsZ5L9cEgHIBaIByzKxOYN9Z1CSb/DleblxR+JN4jquHiO/1IE+uT/gA0RA/Q SHgmMpNaGkxVOvXti5h/QIuII/mIo5LfkzHuOEhOxly37HNoyKqB3saVdCSJMFlR N3lAa77Sa/l+68iRwFyldwxNI42ijm7+vtupSGddsSFrIZUB+gK3Um9SdMEoZuQ= =w5Ym -----END PGP SIGNATURE----- --z4+8/lEcDcG5Ke9S--