From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Noticeably poor Intel GPU performance on 3.3 and 3.4 dom0 kernels Date: Wed, 30 May 2012 10:28:30 -0400 Message-ID: <20120530142830.GE3207@phenom.dumpdata.com> References: <4FC5F2EF.7000004@invisiblethingslab.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <4FC5F2EF.7000004@invisiblethingslab.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: Joanna Rutkowska Cc: "xen-devel@lists.xensource.com" , Marek Marczykowski List-Id: xen-devel@lists.xenproject.org On Wed, May 30, 2012 at 12:14:07PM +0200, Joanna Rutkowska wrote: > Hello, > > 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 trivial > 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... > > In order to make sure that this is not caused by power management set > too strictly, I played with xenpm and made sure to set the following: And are you building with CONFIG_INTEL_IOMMU=y? > 1) xenpm set-scaling-governor performance > 2) xenpm set-max-cstate 0 > > I have verified then that my processor: 1) keeps staying in P0 state > (so, max frequency), and 2) keeps staying in C0 state. > > Those setting didn't change anything regarding the poor graphics > performance, though. > > Any ideas what else I could test to find out the cause of this? > > Thanks, > joanna. > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel