Korganizer 4.9 is now totally unusable since it freeze each time you try to modify a task (changing the due date with the mouse, changing the achievement pourcentage, etc.). The freeze duration time is approximatively ~4 minutes each time you change/create a task. I do have a 13162 ics files in ~/.kde/share/apps/korganizer/data/ and 1319 in /home/acid/.local/share/akonadi/file_db_data/ (but not all ics related). This bug could be rarely seen in 4.8.3, but you could solve it by stopping akonadi and restarting it. The bug does not appear for newly created users. Reproducible: Always Steps to Reproduce: 1. Start kde 2. Launch korganizer 3. Move an existing task to another hour/day 4. Korganizer goes crazy and CPU gets eaten. Expected Results: Move/create the task instantly. Don't eat CPU or brains.
There is a simple 'solution' to fix this problem : Delete the calendar resource in akonadi configuration window, then recreate it with the same informations. Restart Akonadi. Voilà ! Everything should be back to normal. Warning : Some tasks I modified this morning (I completed a recurrent task for instance) disappeared. I guess they were still stored in ~/.local/share/akonadi/file_db_data/ and hence weren't synchronized with the main ics directory. Still, this is a weird 'migration' bug.
What you describe is a workaround, not a solution. Would be great if you could somehow find a way to reproduce the bug (unfortunately, I can't). That would make finding the solution (or possible duplicates of this report) much easier. But as you found out, this is probably an Akonadi issue.
Only happens for tasks ?
As I solved the problem by using the workaround, I can't test that anymore, but I do recall that I haven't tried to move events, only tasks.
I haven't encountered the bug anymore on 4.9.5 and 4.10. Should we close this one ?