From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joanna Rutkowska Subject: Re: Noticeably poor Intel GPU performance on 3.3 and 3.4 dom0 kernels Date: Thu, 31 May 2012 11:15:03 +0200 Message-ID: <4FC73697.20509@invisiblethingslab.com> References: <4FC5F2EF.7000004@invisiblethingslab.com> <4FC614770200007800086D0C@nat28.tlf.novell.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============7100533746776080394==" Return-path: In-Reply-To: <4FC614770200007800086D0C@nat28.tlf.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich Cc: Marek Marczykowski , xen-devel List-Id: xen-devel@lists.xenproject.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --===============7100533746776080394== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigB35C9E40CFC99F47361E5CD8" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigB35C9E40CFC99F47361E5CD8 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 05/30/12 12:37, Jan Beulich wrote: >>>> On 30.05.12 at 12:14, Joanna Rutkowska wrote: >> > I've recently been some newer Dom0 kernels (3.3.5, 3.4) under Xen 4.= 1.2, >> > and have noticed that those kernel noticeably downgrade performance = of >> > (at least) Intel GPUs. This is easily noticeable even on such trivia= l >> > tasks as scrolling a webpage in Firefox or Chrome. This slow GPU >> > performance on 3.3 and 3.4 kernels is in stark contrast with what I = see >> > on 3.2.7 Dom0 kernel, where graphics works just great... >> >=20 >> > In order to make sure that this is not caused by power management se= t >> > too strictly, I played with xenpm and made sure to set the following= : >> > 1) xenpm set-scaling-governor performance >> > 2) xenpm set-max-cstate 0 >> >=20 >> > I have verified then that my processor: 1) keeps staying in P0 state= >> > (so, max frequency), and 2) keeps staying in C0 state. >> >=20 >> > Those setting didn't change anything regarding the poor graphics >> > performance, though. >> >=20 >> > Any ideas what else I could test to find out the cause of this? > To check whether the DRM drivers' supposedly more extensive > use of the DMA API is the reason, could you check whether the > performance is as bad with "mem=3D4G" on the Xen command line? With mem=3D4G xen option, the graphics performance is just as poor as wit= hout. joanna. --------------enigB35C9E40CFC99F47361E5CD8 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJPxzaXAAoJEDaIqHeRBUM0e+gH/j1nu4oqExRffvPgJntr2tan 0u7sA5tSrH8jijOUk61OBmd9/oAwQt8asLPcxX1rbqKP73dMe6/nFxgZO/PBGjiY hBwlktnS/s+lr+rf/aMIBDAZJmrB0QLFX6GcFZLbdyxq+xV3WeEZ1XoxPPPG41PU 1anjOyryHT+hYwqwEVDCME6Od8+dXuJRia9TEN0+YCHHMxzZ9MdJ1lb+5SXsz6Tg WJNr8mNf04diG8m3DdQ1lSUqFAJUxSMbjG6WrgTqCwQw46FvchjHCWD9I+/0unwd VTfaolecmQv4w8Qw5U/8EvQQLXVURs39/wL6Elu+//GMJY/dapsVLxY6zrdS6bg= =ftK2 -----END PGP SIGNATURE----- --------------enigB35C9E40CFC99F47361E5CD8-- --===============7100533746776080394== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel --===============7100533746776080394==--