** Description changed: On some devices (mako at least) it's possible to force double buffering and it will often keep up: - restart unity8 QML_NO_TOUCH_COMPRESSION=1 MIR_SERVER_NBUFFERS=2 + restart unity8 QML_NO_TOUCH_COMPRESSION=1 MIR_SERVER_NBUFFERS=2 Curiously however it only keeps up smoothly (eg. during a dash scroll) while you're touching the screen. If you lift off or fling the dash then it immediately stutters, quite badly. So the issue is not that the device can't keep up with double buffering. It seems more like we're not keeping the kernel sufficiently awake and it's clocking down prematurely, as soon as we're not touching it. Certainly adjusting the variables in: - /sys/devices/system/cpu/cpu0/cpufreq + /sys/devices/system/cpu/cpu0/cpufreq it is possible to raise the performance and minimum frequency to make double buffering smooth. The challenge of this bug is to find a way in Mir/QtMir to keep the kernel more awake so it doesn't clock down when we need smooth animations and we're not touching the screen. + + Also note that while this bug sounds like bad news for mako, mako is + actually the best performing device. Others like arale don't reliably + speed up in response to short touches.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1488386 Title: [performance] Double buffering is only smooth while you're touching it To manage notifications about this bug go to: https://bugs.launchpad.net/mir/+bug/1488386/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
