From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Vivier Subject: Re: [ANNOUNCE] kvm-14 release Date: Wed, 21 Feb 2007 15:55:10 +0100 Message-ID: <45DC5D4E.5000300@bull.net> References: <45D98390.6060001@qumranet.com> <45DA25D9.1060509@aurel32.net> <45DA9FFA.2020009@qumranet.com> <45DB7514.3040409@aurel32.net> <45DBFD6E.2060507@qumranet.com> <45DC51E3.7010205@aurel32.net> <45DC54B5.9080608@qumranet.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1991990502==" Cc: kvm-devel , =?ISO-8859-1?Q?S=E9bastien_Dugu=E9?= To: Avi Kivity Return-path: In-Reply-To: <45DC54B5.9080608-atKUWr5tajBWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --===============1991990502== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig76787E297C6E604A01262691" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig76787E297C6E604A01262691 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Avi Kivity wrote: > Aurelien Jarno wrote: >> =20 >>> What is your disk image file format, or are you using a partition? >>> =20 >> I am using a raw image file on an ext3 partition. >> >> =20 >>> Do the results change (on kvm-14) if you pin the guest to a core with= =20 >>> 'taskset 1 qemu ...' >>> =20 >> Bingo. It now works even faster than kvm-13! >> >> real 0m22.307s >> user 0m13.935s >> sys 0m4.720 >> >> =20 >=20 > I'm guessing this is due to the glibc aio implementation, which uses=20 > threads instead of true aio. The threads may cause the vcpu to migrate= =20 > frequently from one code to another. >=20 > There are two possible solutions: >=20 > - use native aio from http://www.bullopensource.org/posix/. I think=20 > the aio signal patches are not yet in, so this may not work. > - teach the scheduler about the cost of migrating vcpus > The first approach will solve itself eventually, though slowly if the=20 > current slow rate of aio merging continues. We'll have to do the secon= d. >=20 if you prefer the first one, S=E9bastien will release very soon aio patch= es for 2.6.20 with an up-to-date libposix-aio. [advertising] Keep an eye on the bullopensource website. [/advertising] :-P Regards, Laurent --=20 ------------- Laurent.Vivier-6ktuUTfB/bM@public.gmane.org -------------- "Any sufficiently advanced technology is indistinguishable from magic." - Arthur C. Clarke --------------enig76787E297C6E604A01262691 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.7 (GNU/Linux) iD8DBQFF3F1S9Kffa9pFVzwRAghoAJkBUc+qx/IqGEqyYjYDw1HzlbNbHACgmJ0g PCYSj9H0+NdwBi6EHXtPo3U= =oQp6 -----END PGP SIGNATURE----- --------------enig76787E297C6E604A01262691-- --===============1991990502== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV --===============1991990502== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ kvm-devel mailing list kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org https://lists.sourceforge.net/lists/listinfo/kvm-devel --===============1991990502==--