[Jaunty] My system freezes several times a day; Ctrl+Alt+Backspace doesn't work.

[Gustavo Narea]

I have a Dell XPS M1330 and Kubuntu Jaunty is _unusable_ here*. It freezes _very_ often, with no obvious pattern, so I can't suggest a package; and I don't use 3D effects at all, so I don't think this is the same as Bug #359392.

There are a few interesting things in these freezes:
 1.- I can still move the mouse cursor normally, but clicks don't work -- because the applications, the panels, the system tray... are all frozen.
 2.- I can't restart X with Ctrl+Alt+Backspace. (Yes, I know it's disabled by default, but I re-enabled it and it does work when the system is not frozen.)
 3.- Many times it happens when I'm using Kmail or Konqueror. There's no URL or anything like that I can point you to to try to reproduce this bug, because they're no obvious pattern -- It's even crashed when I was reading a simple HTML document locally.

The computer can freeze after a few minutes or after hours being on, it's absolutely unpredictable.

* It's absolutely unusable because I always loose what I'm doing and I don't know how to avoid these freezes. I also think it could damage my hard disk, because when it's frozen I just can press the power button to turn it off.

[Mathieu Comandon (strycore)]

can you ssh to your laptop from another machine ?

[Gustavo Narea (gnarea)]

Hi, Mathieu. Yes, I can.

[Mathieu Comandon (strycore)]

can you run a top or sudo top to see if there is a process that eats all the CPU ?

Can you also give the output of dmesg (also in the ssh session) ?

[Balázs Németh (atyauristen)]

i can confirm the same, using lenovo thinkpad r61i.
everything seems running fine in background after freezing, downloading continues, music still playing, but you cannot interact anymore.

[Gustavo Narea (gnarea)]

@Mathieu: I don't think it's a program eating the CPU, as you may find in the attachments, because the computer never gets slow: It just stops responding suddenly.

@atyauristen: It could be the same problem, but I can't remember if music continues playing or if downloads continue. :(

[Gustavo Narea (gnarea)]

@Mathieu: You were right, there was a program eating the CPU. This wasn't shown in the attachments above because I took ~3 minutes to turn on the other computer and log the output requested after the freeze.

But today it crashed and the other computer was already on, so I could check `top` immediately and it showed that kontact was using "101%" of the CPU. It surprised me because everything was working fine, it must have reached that point in one millisecond.

I logged that and came to launchpad.net to attach such file, but as usual my computer froze (this time without kontact open) and I went to the other computer to log `top` with the new freeze, but by mistake I overrode the previous file -- and this time, top showed no program using more than 10% of the CPU.

[Gustavo Narea (gnarea)]

Downgrading xserver-xorg-video-intel as explained here https://wiki.ubuntu.com/ReinhardTartler/X/RevertingIntelDriverTo2.4 fixes the freezes, but introduces more bugs (Can't play 3D games anymore, window transparencies don't work anymore, etc).

Should I include the Dell Ubuntu Project in this bug?

[Gustavo Narea (gnarea)]

A workaround for this bug is to use UXA, at least on my system. I haven't noticed side-issues with this solution, it works like a charm.

Given that it's obviously a problem with the default version of xserver-xorg-video-intel, I've marked this as a duplicate of Bug #359392.