https://bugs.kde.org/show_bug.cgi?id=451059
Bug ID: 451059 Summary: Okular freezes for up to 10 seconds when loading a document or switching windows Product: okular Version: 21.12.2 Platform: Debian unstable OS: Linux Status: REPORTED Severity: major Priority: NOR Component: general Assignee: okular-devel@kde.org Reporter: amaury.po...@gmail.com Target Milestone: --- Created attachment 147249 --> https://bugs.kde.org/attachment.cgi?id=147249&action=edit D-BUS log of a such an instance I have a large number of okular instances running (typically 20 or more) and very often either loading a new document or just switching between windows (or switching between virtual desktops) will make okular completely freeze for a long time. Quite regularly, the freeze is short enough to be an annoyance (a couple of seconds), but every now and then, it can freeze for 10 seconds and more. I tried to debug the code myself but I am out of my depth. I got to suspect, however, that it is related to okular asking other okular instances questions over D-BUS, specifically the canOpenDocs call. I attach a D-BUS trace showing an instance when opening a document will trigger several very slow canOpenDocs calls (5 seconds). Unfortunately, I haven't found yet a 100% recipe to reproduce it but clearly: 1) it only happens with many okular instances running 2) switching virtual desktops seems to make it worse Finally, the bug is not new, I has been happening for some time but progressively got worse as my number of open documents has increased recently. I happy to provide more logs/recompile stuff if needed, I just don't really know where to start at the moment. STEPS TO REPRODUCE 1. open lots of okular documents (I use PDFs), the size of the PDFs does not seem to matter 2. switch between windows/desktops 3. open a new document, hope to reproduce the bug, otherwise close it 4. return to step 2 OBSERVED RESULT opening/switching to a windows will take anywhere between 2 to 10 seconds EXPECTED RESULT should be almost instantenous SOFTWARE/OS VERSIONS Linux: 5.16.0-3-amd64 KDE Plasma Version: 5.24.2 KDE Frameworks Version: 5.90.0 Qt Version: 5.15.2 ADDITIONAL INFORMATION -- You are receiving this mail because: You are the assignee for the bug.