From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6291 invoked by alias); 28 Mar 2013 13:09:38 -0000 Mailing-List: contact cygwin-xfree-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-xfree-owner@cygwin.com Reply-To: cygwin-xfree@cygwin.com Mail-Followup-To: cygwin-xfree@cygwin.com Received: (qmail 6239 invoked by uid 89); 28 Mar 2013 13:09:29 -0000 X-Spam-SWARE-Status: No, score=2.9 required=5.0 tests=AWL,BAYES_00,DONT_USE_RAW_EMAIL_IN_BODY,FREEMAIL_FROM,KHOP_THREADED,RCVD_IN_DNSWL_NONE,RCVD_IN_HOSTKARMA_YE,RP_MATCHES_RCVD autolearn=no version=3.3.1 Received: from snt0-omc2-s6.snt0.hotmail.com (HELO snt0-omc2-s6.snt0.hotmail.com) (65.55.90.81) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Thu, 28 Mar 2013 13:09:26 +0000 Received: from SNT401-EAS206 ([65.55.90.73]) by snt0-omc2-s6.snt0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675); Thu, 28 Mar 2013 06:09:25 -0700 X-EIP: [X3PVWU+TT648hCfo4qRVcTxw7GgVY2VZ57DEqXIMsrA=] Message-ID: Reply-To: From: "Aaron A. Kelley" To: "'cygwin-xfree'" References: <51530C21.8000203@dronecode.org.uk> In-Reply-To: <51530C21.8000203@dronecode.org.uk> Subject: RE: Cygwin/X causes NVIDIA GPU to turn on in Optimus systems Date: Fri, 29 Mar 2013 13:06:00 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-SW-Source: 2013-03/txt/msg00031.txt.bz2 Hi, thanks for your reply. Very helpful. I checked the XWin.0.log and found: [ 73510.875] GL_VERSION: 4.3.0 [ 73510.875] GL_VENDOR: NVIDIA Corporation [ 73510.875] GL_RENDERER: Quadro K5000M/PCIe/SSE2 So, it looks like XWin is running on the NVIDIA GPU even though the Intel GPU is set at the default rendering device (both for all apps by default and by XWin.exe specifically) in the NVIDIA control panel. I'll see if I can get NVIDIA to comment on this at all but who knows if I'll actually be able to get in touch with anyone. Anyway, I don't need OpenGL for the programs that I use, so I checked into using the -nowgl parameter that you suggested and that took care of it. With -nowgl set, XWin happily runs on the Intel GPU and Optimus does not engage. Thanks, -- Aaron -----Original Message----- From: Jon TURNEY [mailto:jon.turney@dronecode.org.uk] Sent: Wednesday, March 27, 2013 11:11 AM To: cygwin-xfree@cygwin.com Cc: aaronkelley@hotmail.com Subject: Re: Cygwin/X causes NVIDIA GPU to turn on in Optimus systems On 26/03/2013 15:58, Aaron A. Kelley wrote: > I usually leave Cygwin/X open on my machine because I use it to access GUI > apps running in SSH terminals from time to time. Today I noticed that in an > Optimus environment, it is causing the NVIDIA GPU to kick in, which causes > the NVIDIA GPU to stay powered on when maybe it doesn't need to. > > http://stuff.aaron-kelley.net/2013/03/cygxoptimus.png > > I went to the NVIDIA control panel and set xwin.exe specifically to use the > integrated GPU but it still says that xwin.exe is running on the NVIDIA GPU > when I run it. Cygwin/X must be doing something unusual at initialization > that makes the NVIDIA card feel like it has to kick on. I don't have to > actually launch any X windows to see this occur, it happens moments after I > launch the Cygwin/X server. The Cygwin X server doesn't do anything special (and specifically, doesn't do any of the things listed in [1] to explicitly use the high-performance GPU), so if it's being allowed to use OpenGL on the high-performance GPU despite the application profile you have created, I would say that might be a bug in the optimus driver. Note that this policy does belong in your hands, not in XWin, as it cannot know if you are going to be running any X programs using OpenGL, and if you are, if you want high-performance rendering in them at the cost of additional power usage. As a workaround, you could start the X server with the -nowgl option added, which should prevent any use of native OpenGL, forcing the use of software rendering using mesa and see if that helps. > I haven't been able to find anyone else mentioning this. It may be because > Optimus configurations aren't very common. This also means that this issue > may be tricky to track down. I'm not sure if it will be easy to find > someone who knows about Cygwin/X development who also has access to an > Optimus environment. This might be something that has to go for NVIDIA for > them to fix in their drivers, but it'd be nice to know a little more about > the issue before trying to get in touch with them. > > I'm interested in doing anything I can do help address this but I don't know > where to begin, so I'm welcoming your feedback. For a start, you could look for the GL_VENDOR and GL_RENDERER lines in /var/log/xwin/XWin.0.log to confirm that XWin also thinks it is using the high-performance GPU. [1] http://developer.download.nvidia.com/devzone/devcenter/gamegraphics/files/Op timusRenderingPolicies.pdf -- Jon TURNEY Volunteer Cygwin/X X Server maintainer -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://x.cygwin.com/docs/ FAQ: http://x.cygwin.com/docs/faq/