(In reply to comment #93) > The bad part is - while before I've been getting 3.7Mchar/s in x11perf > -aa10text - now it's like 1.3Mchar/s so significantly slower.
That's the sacrifice, we have to stop sending commands to the GPU and wait for it complete those in flight (quite frequently). Or else new rectangles overwrite vertex entries still being used by later entries > So the question here would be - isn't the corruption based on triangle > surface size ? So i.e. GPU is able to process a lot of small ones - but has > bug with bigger ones ? > > Maybe a cheap test would be to flush when some longer triangle edge is > pushed in ? Not really, you have to predict when a VUE being used by the end of the pipeline will be overwritten by a new rectangle at the start of the pipeline. This is completely internal state - the primitive command we want to feed to the GPU can contains thousands of rectangles. Instead of counting rectangles, you want to start counting fragments (actually texel reads since that will be the ratelimiting factor) and flush if we queue up too much work for the GPU. If you also model how fast the gpu is retiring fragments so that you can predict how much work is in flight, you could further reduce flushes... We still need to stop the gpu and wait for it to complete. No matter how finely you do it, it will sacrifice throughput and latency. It's a workaround. I still live in hope that after all these years we missed some configuration detail required for gen4. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/1098334 Title: [gen4 sna] Font corruption in Chromium tab bar Status in X.org xf86-video-intel: In Progress Status in “xserver-xorg-video-intel” package in Ubuntu: Triaged Bug description: After enabling the SNA acceleration method and rebooting, I noticed that graphical glitches appeared in the letters on Chromium's tab bar during the mouse hover animation. I've attached a screenshot illustrating this, particularly with the letter "g" in the screenshot. ProblemType: Bug DistroRelease: Ubuntu 13.04 Package: xorg 1:7.7+1ubuntu4 ProcVersionSignature: Ubuntu 3.7.0-7.15-generic 3.7.0 Uname: Linux 3.7.0-7-generic x86_64 ApportVersion: 2.8-0ubuntu1 Architecture: amd64 Date: Thu Jan 10 16:00:55 2013 InstallationDate: Installed on 2012-09-24 (107 days ago) InstallationMedia: Kubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120822.2) MarkForUpload: True SourcePackage: xorg UpgradeStatus: Upgraded to raring on 2012-09-25 (107 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/xserver-xorg-video-intel/+bug/1098334/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp