Version: 4.1.0 (using 4.1.2 (KDE 4.1.2), Kubuntu packages) Compiler: cc OS: Linux (i686) release 2.6.27-7-generic I am converting to kde4 and have a reasonably large calendar file (>35000 lines). I ran into issues described in bug 165212, and ran a migration script to convert all events to my local timezone. The script appears to have worked correctly, but korganizer is now very slow to parse the std.ics file (20s vs 4s when the file was encoded in UTC). While this could be an issue specific to this migration script, it seems just as likely that korganizer encounters performance problems when all events are encoded in the user's local time rather than UTC. Since this appears to be the new default, it seems possible that performance problems will become widespread once people start having large calendar files in the new format. I can email the std.ics file to someone offline (I don't want it to be public) if someone wants it for profiling purposes.
Recently there has been a lot of work put into making KOrganizer faster. So I will close this bug. Please reopen if you still find KOrganizer slow with KDE 4.2. Some speed fixups will make it into KDE 4.1.4 too.