In the latest releases of KDE Plasma 5 (5.13.5 and 5.14.X) I observed some severe performance slowdowns when using some parts of the system; for example when trying to change the appearance of the cursor in system settings it takes really long for anything to respond, however the rest of the system is alright (actually the cursor settings are slow since the style was upgraded). The same can be seen when using Discover (I have to use Gnome Software Center because Discover is impossible to use on my Intel GPU at the moment). I don't what causes the issue exactly but I suspect it has something to do with QT or some acceleration issues on older GPUs. I tested this on a Intel 945G GPU (Using i915 driver). SOFTWARE/OS VERSIONS Linux: Kubuntu 18.10 (Linux 4.18.0-10) KDE Plasma Version: 5.14.3 (Kubuntu backports) KDE Frameworks Version: 5.51.0 Qt Version: 5.1.1
So use of QtQuick is slow, especially when using the desktop theme where we have large texture uploads. Probably means we have a software GL driver. They do suck. You can try kcmshell5 qtquicksettings and selecting the software backend. This means we avoid GL and use a slower software fallback, but that's often quicker than using GL that in turn is software emulated. Let me know if it helps.
(In reply to David Edmundson from comment #1) > So use of QtQuick is slow, especially when using the desktop theme where we > have large texture uploads. > > Probably means we have a software GL driver. They do suck. > > You can try > > kcmshell5 qtquicksettings > > and selecting the software backend. > > This means we avoid GL and use a slower software fallback, but that's often > quicker than using GL that in turn is software emulated. > > Let me know if it helps. That actually solved the problem immediatly. Thanks! I think this should be reported to QT to see if they can fix it.
(In reply to JORGETECH from comment #2) > (In reply to David Edmundson from comment #1) > > So use of QtQuick is slow, especially when using the desktop theme where we > > have large texture uploads. > > > > Probably means we have a software GL driver. They do suck. > > > > You can try > > > > kcmshell5 qtquicksettings > > > > and selecting the software backend. > > > > This means we avoid GL and use a slower software fallback, but that's often > > quicker than using GL that in turn is software emulated. > > > > Let me know if it helps. > > That actually solved the problem immediatly. Thanks! > > I think this should be reported to QT to see if they can fix it. I forgot to say that Discover is still slow. Does it have something to do with Kirigami?
There's nothing Qt can do. I'll check discover loads the KDE quick settings overrides.
Git commit d783ebd003c9ffc66a0fdd5aca28045f10bf9937 by David Edmundson. Committed on 12/11/2018 at 11:21. Pushed by davidedmundson into branch 'master'. Load KDE QtQuickSettings in Discover Summary: As per other QtQuick parts of Plasma Test Plan: Compiles. Code is copy pasted from working projects. Reviewers: #plasma, apol Reviewed By: apol Subscribers: apol, plasma-devel Tags: #plasma Differential Revision: https://phabricator.kde.org/D16811 M +1 -1 CMakeLists.txt M +1 -0 discover/CMakeLists.txt M +2 -0 discover/main.cpp https://commits.kde.org/discover/d783ebd003c9ffc66a0fdd5aca28045f10bf9937