Comment 243 for bug 355155

After Andreas' comments about multi core processors I switched off one of my Athlon dual cores via the bios. Since then (about four days now) I have had no freezes despite switching Compiz effects back on and throwing every video loading I could at it. In fact the system seems to run faster, albeit it slows down when really heavy loads are applied to the processor. Sometimes the processor load reaches 100% (monitored via Htop) but the system doesn't freeze.

I had one site that I could guarantee would freeze the machine at http://www.tbyc.org/weather-station/ but even this doesn't seem to happen now. With both cores running the freezes happened with both Firefox and Opera when viewing pages with a Flash component (not all, the BBC site was OK).

Using Htop I could see the process/command consuming the processor resources was:
/usr/X11R6/bin/X :0 -br -audit 0 -auth /var/lib/gdm/:0.Xauth -nolisten tcp vt7
Haven't a clue what that represents but here's the interesting bit. If I was patient and immediately closed Firefox or Opera then that process appeared to release the resources and processor loads dropped to 3 or 4%. However if Firefox or Opera were then reloaded the processor resources were immediately 'snatched' by the above process - on the same core. Everything then slowed down to freeze point again. This was repeatable time and time again.

Applying layman's logic (I'm no expert) the problem seems to be in the handling of multi core loadings either by the bios, the hardware or Linux. I err to the latter as I had none of these problems with Ubuntu 8.04.

Hope this ramble helps the experts.

As an aside, is there any tool that can monitor and log the actual steps that the operating system/hardware is following?