I upgraded my laptop to Ubuntu 9.04 Jaunty in the hope that it would fix the “I have no memory of your last session” problem that 8.10 introduced. Everything went smoothly, and everything seems to work well.
Except one thing.
The CPU utilisation was 100% on one core. I’m lucky this is a dual core laptop, or the thing would likely be unusable.
It turns out that the problem was the remote desktop process: vino-server. Killing vino-server meant that the Xorg process was no longer chewing up 14% CPU (according to top) and made the CPU usage drop back to next to nothing when idle. As it should be.
I found the hint at this thread in launchpad. I hope this tip helps you if you have this problem. I doubt I would have figured it out on my own, so here’s to the power of the internet and sharing information!