Intel OpenGL/Vulkan Developers Join #intel-3d

[duby229]

That's not what I said. Tearing in Firefox is Firefox's fault, not the display driver's fault, especially on Linux where they don't use GPU acceleration at all.

Although correct firefox is (still) unaccelerated it does not tear on the modesetting driver. If you see something on screen that means it was written to the framebuffer.

[linuxgeex]

I'd actually recommend you to rather deinstall the intel ddx driver. Xorg will then use the modesetting driver with glamor, which is way more stable. That's what all radeonsi cards do, aswell as what happens on wayland (using glamor for xwayland).

Edit: that's what more recent distributions do, see http://www.phoronix.com/scan.php?pag...ndon-Intel-DDX and https://www.phoronix.com/scan.php?pa...tel-DDX-Switch

Edit2: you probably want to have the hwe-stack installed if you do it https://wiki.ubuntu.com/Kernel/LTSEnablementStack

I would like to agree with you, but sadly glamour uses more battery power (try using power monitor tools with SNA vs Glamor and you'll see what I mean - and I pay a premium for a laptop with long battery life so I'll choose not to throw that money away) and it lacks some xrandr features (--scale) which make it useless to me because I need --scale as an accessibility feature (I have keratoconus and my acuity changes rapidly throughout the day so to get work done I need to routinely adjust the apparent display resolution, and --scale again does this with minimal battery impact, unlike the scaling feature of compositing desktops like XFCe4, Unity, GNOME, and compiz).

Hmm... but for a Kodi set-top-box media player, sure. Maybe in 2 years when I get around to upgrading this thing to the next LTS. :-)

[linuxgeex]

Sure he can, if he wants the shittiest display experience he can possibly imagine. I'm actually quite surprised he claims he eliminated tearing, I don't think that's actually possible with Intel's DDX. I'm sure he just needs to open a browser and scroll to realize it isn't actually fixed for all scenarios. He really should be on the modesetting DDX. Intel desperately needs to make modesetting the default DDX for their products immediately.

DRI3/SNA/tearfree is flawless. Setting javascript to turn alternate black/white backgrounds for a page at 60hz results in no tearing. That's my cardinal test. Of course, caveats emptor for software that makes no attempts whatsoever to present complete frames to the desktop compositor. Then all bets are off.

FF 55.0.2 and Chromium 60.0.3112.78 don't tear as of now on the old IVB machine with the above mentioned config file in place.

Use this script at developer console to test for tearing in the browser:

new function(){
  var a=0, hz=60, f=function(){
    var color = (a++&1)?"#FFF":"#000";
    document.body.style.cssText="background:"+color;
  }
  setInterval(f,1000/hz);
}();

Hit reload to stop it.

[linuxgeex]

That's not what I said. Tearing in Firefox is Firefox's fault, not the display driver's fault, especially on Linux where they don't use GPU acceleration at all.

Firefox doesn't tear here. Flash tears within firefox, but that's not Firefox's fault. That's flash rendering directly instead of passing the frames to Firefox to manage. If you set wmode=transparent then flash stops tearing but the frame rate drops. Youtube doesn't tear for me. See https://www.youtube.com/watch?v=9hIRq5HTh5s and if that tears for you then try installing the file I mentioned above, reboot (or systemctl restart lightdm.service from a console) and all will be perfect.

[duby229]

DRI3/SNA/tearfree is flawless. Setting javascript to turn alternate black/white backgrounds for a page at 60hz results in no tearing. That's my cardinal test. Of course, caveats emptor for software that makes no attempts whatsoever to present complete frames to the desktop compositor. Then all bets are off.

FF 55.0.2 and Chromium 60.0.3112.78 don't tear as of now on the old IVB machine with the above mentioned config file in place.

Use this script at developer console to test for tearing in the browser:

new function(){
var a=0, hz=60, f=function(){
var color = (a++&1)?"#FFF":"#000";
document.body.style.cssText="background:"+color;
}
setInterval(f,1000/hz);
}();

Hit reload to stop it.

I just don't get how you can bare SNA. It's so buggy. Maybe it's just my particular hardware that doesn't work well with SNA, but maybe yours does. I assume that's a real possibility.

[linuxgeex]

I just don't get how you can bare SNA. It's so buggy. Maybe it's just my particular hardware that doesn't work well with SNA, but maybe yours does. I assume that's a real possibility.

I've never had any issues with SNA on any device I've owned. It's fast, the X server uses less memory, the system uses less battery power, it doesn't adversely impact other 3D app performance. The only display issue I've ever had was with GTK3 corrupting fonts when I suspended one of my machines, but that had nothing to do with SNA and everything to do with GTK3 caching font data in an invisible part of the framebuffer that isn't preserved when the system goes to sleep.

Maybe you had different experiences. Given that SNA has been the platform default on Ubuntu for at least 4 years, it's probably not as bad as you think it is for the rest of us. I hear that Intel has dropped support for it and Glamour is what we get from 17.04 forward, so yay for you.

Actually, I'm intrigued, because you sound so sure of yourself that, given the power to control system configurations for other users, you would have chosen to make this change without even consulting them. That would have had a pretty crappy impact on my life. So where are some specific test cases supporting your claim that "It's so buggy" that Glamour's poor performance is somehow an upgrade? I can sure provide plenty of examples of how Glamour introduces feature and performance regressions: