Googling around I found this: https://bugs.freedesktop.org/show_bug.cgi?id=87478 which puts some blame on Qt's shaders for distance field text rendering.
Happier news is that Qt has options to either use a lower quality distance field rendering approach (fewer ALU instructions) or disabling distance field approach completely. Env vars to play with (I don't have the hardware to test with): QSG_DISTANCEFIELD_ANTIALIASING=subpixel/subpixel-lowq/gray (subpixel the default I believe) QML_DISABLE_DISTANCEFIELD=1 I would also suspect the UbuntuShape is guilty, we probably need a low quality version of it too. ** Bug watch added: freedesktop.org Bugzilla #87478 https://bugs.freedesktop.org/show_bug.cgi?id=87478 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unity8 in Ubuntu. https://bugs.launchpad.net/bugs/1580792 Title: Unity8 on Intel Atoms performs poorly Status in unity8 package in Ubuntu: Confirmed Bug description: (problem forked from bug 1549455) Unity8 on Intel Pineview performs very poorly. Frame times appears to be up to 900ms, Qt's renderer thread using 100% CPU. Running unity8 with MESA_DEBUG=1 EGL_LOG_LEVEL=debug reveals a few MESA errors: http://paste.ubuntu.com/16344427/ Quoting @vanvugt "Those Mesa errors "Mesa: User error:" all look like OpenGL features that Unity8 is hitting but mir-demos don't. So those gl calls are also good candidates for explaining poor performance, especially if Mesa is falling back to software rendering for them." Since Qt tends to perform just fine on that hardware in X11, something isn't right. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unity8/+bug/1580792/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
