From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <50FDCB83.4060707@xenomai.org> Date: Tue, 22 Jan 2013 00:13:07 +0100 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <1358809464.75419.YahooMailNeo@web140601.mail.bf1.yahoo.com> In-Reply-To: <1358809464.75419.YahooMailNeo@web140601.mail.bf1.yahoo.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai] x86 Linux with xenomai and i915 graphics stall List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: A User Cc: "xenomai@xenomai.org" On 01/22/2013 12:04 AM, A User wrote: > I'm trying to run a Linux/Xenomai system with Ubuntu 12.04 LTS > distro including X Window System on an Intel x86 board. > > linux: 3.2.21 > xenomai: 2.6.1 > i-pipe Patch: 3.2.21-x86-1 > > When I run with CONFIG_PCI_MSI turned off, I get good Xenomai latency, > but the X Window System is unusable. With MSI turned on, graphics is > solid, but latency jumps to about 450 usec when I run glxgears > (instead of avg 10 usec, max 50 usec). > > I believe that if I want to use X Window system in a recent x86 system > with motherboard graphics, the most popular choice (the only choice?) > is i915. > > Do you have any advice on how I can run with i915 and Xenomai with > this hardware and software? That is strange, I have tested xenomai on my workstation which is a core i5 and also has an i915, I have been playing video and running other opengl apps (including glxgears) and dit not observe high latencies. I was using Linux 3.5.7 patched with Xenomai 2.6.2, but I guess it should not make any difference. My core i5 is a "sandy bridge" though, so should have an intel graphics HD3000 not 4000. I would suggest enabling the I-pipe tracer in the kernel configuration in order to find what is taking so long. Anyway, turning on CONFIG_PCI_MSI is recommended these days. Also, have you read the troubleshooting guide about SMIs? If you can not run an accelerated X server, there is always the solution to revert to disable the acceleration in the server configuration, as is documented in the troubleshooting guide as well. -- Gilles.