From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:36777) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TVg9H-0005in-JU for qemu-devel@nongnu.org; Tue, 06 Nov 2012 05:12:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TVg9D-0007tr-D5 for qemu-devel@nongnu.org; Tue, 06 Nov 2012 05:12:47 -0500 Received: from mout.web.de ([212.227.15.4]:61396) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TVg9D-0007tg-32 for qemu-devel@nongnu.org; Tue, 06 Nov 2012 05:12:43 -0500 Message-ID: <5098E288.9060505@web.de> Date: Tue, 06 Nov 2012 11:12:24 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <24E144B8C0207547AD09C467A8259F75577D5BE5@lisa.maurer-it.com> <24E144B8C0207547AD09C467A8259F75577E90B9@lisa.maurer-it.com> <24E144B8C0207547AD09C467A8259F75577EC2E1@lisa.maurer-it.com> <5098D7B9.9020205@web.de> <24E144B8C0207547AD09C467A8259F75577EC39A@lisa.maurer-it.com> In-Reply-To: <24E144B8C0207547AD09C467A8259F75577EC39A@lisa.maurer-it.com> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigF617F75BCCD389B4B50E8F15" Subject: Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Dietmar Maurer Cc: Stefan Hajnoczi , Peter Lieven , "qemu-devel@nongnu.org" , "Michael S. Tsirkin" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigF617F75BCCD389B4B50E8F15 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 2012-11-06 10:46, Dietmar Maurer wrote: >>> This obviously breaks vhost when using multiple cores. >> >> With "obviously" you mean you already have a clue why? >> >> I'll try to reproduce. >=20 > No, sorry - just meant the performance regression is obvious (factor 20= to 40). >=20 OK. Did you try to bisect over qemu-kvm as well? I'm wondering if there was a version of vhost there that didn't have this regression but was also using direct IRQ delivery inside the kernel. Jan --------------enigF617F75BCCD389B4B50E8F15 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iEYEARECAAYFAlCY4ogACgkQitSsb3rl5xR81QCfcGPoI0toFMGfnA1ILD+DTBST XO4AmgPtF1nS4Vjhqqrftz2KN6y7c3ny =tKu5 -----END PGP SIGNATURE----- --------------enigF617F75BCCD389B4B50E8F15--