Frequent crashing

[AVHATION]

I am experiencing frequent crashing, not apparently linked to any particular keyboard action. System Log File Viewer shows that immediately before each crash Pulse Audio was trying to do something; this is a typical example:
Aug 19 17:50:48 henry-desktop kernel: [ 16.645113] type=1505 audit(1282236648.852:8): operation="profile_replace" pid=642 name="/usr/lib/connman/scripts/dhclient-script"
Aug 19 17:50:48 henry-desktop kernel: [ 16.735389] type=1505 audit(1282236648.940:9): operation="profile_load" pid=708 name="/usr/bin/evince"
Aug 19 17:50:49 henry-desktop kernel: [ 16.827981] type=1505 audit(1282236649.032:10): operation="profile_load" pid=708 name="/usr/bin/evince-previewer"
Aug 19 17:50:49 henry-desktop kernel: [ 16.849772] type=1505 audit(1282236649.056:11): operation="profile_load" pid=708 name="/usr/bin/evince-thumbnailer"
Aug 19 17:50:49 henry-desktop kernel: [ 17.376171] apm: BIOS not found.
Aug 19 17:50:58 henry-desktop pulseaudio[1045]: ratelimit.c: 2 events suppressed
Aug 19 17:51:21 henry-desktop pulseaudio[1296]: ratelimit.c: 4 events suppressed
Aug 19 17:51:27 henry-desktop pulseaudio[1296]: ratelimit.c: 1 events suppressed


Above are the current latest entries, before the next crash. I have reinstalled Ubuntu and updated and upgraded it to 10.4. In an effort to solve the problem prior to that, I deleted all references to Pulseaudio in Synaptic with the apparent result that sometime later the login screen would not work which why I had to resort to reinstalling Ubuntu. The symptom has carried over from my previous machine to this one; the only common hardware is the second hard drive which contains my files, no OS. The first drive has both Win XP and Ubuntu in different partitions. Of possible relevance may be that although number lock is set to on in the BIOS, I have to set it myself after starting. One final clue, to restart the frozen machine I have been holding Control Atl Delete for several seconds with apparent success.

[sydbat]

I am experiencing frequent crashing, not apparently linked to any particular keyboard action. System Log File Viewer shows that immediately before each crash Pulse Audio was trying to do something; this is a typical example:
Aug 19 17:50:48 henry-desktop kernel: [ 16.645113] type=1505 audit(1282236648.852:8): operation="profile_replace" pid=642 name="/usr/lib/connman/scripts/dhclient-script"
Aug 19 17:50:48 henry-desktop kernel: [ 16.735389] type=1505 audit(1282236648.940:9): operation="profile_load" pid=708 name="/usr/bin/evince"
Aug 19 17:50:49 henry-desktop kernel: [ 16.827981] type=1505 audit(1282236649.032:10): operation="profile_load" pid=708 name="/usr/bin/evince-previewer"
Aug 19 17:50:49 henry-desktop kernel: [ 16.849772] type=1505 audit(1282236649.056:11): operation="profile_load" pid=708 name="/usr/bin/evince-thumbnailer"
Aug 19 17:50:49 henry-desktop kernel: [ 17.376171] apm: BIOS not found.
Aug 19 17:50:58 henry-desktop pulseaudio[1045]: ratelimit.c: 2 events suppressed
Aug 19 17:51:21 henry-desktop pulseaudio[1296]: ratelimit.c: 4 events suppressed
Aug 19 17:51:27 henry-desktop pulseaudio[1296]: ratelimit.c: 1 events suppressed


Above are the current latest entries, before the next crash. I have reinstalled Ubuntu and updated and upgraded it to 10.4. In an effort to solve the problem prior to that, I deleted all references to Pulseaudio in Synaptic with the apparent result that sometime later the login screen would not work which why I had to resort to reinstalling Ubuntu. The symptom has carried over from my previous machine to this one; the only common hardware is the second hard drive which contains my files, no OS. The first drive has both Win XP and Ubuntu in different partitions. Of possible relevance may be that although number lock is set to on in the BIOS, I have to set it myself after starting. One final clue, to restart the frozen machine I have been holding Control Atl Delete for several seconds with apparent success.

If you can, remove the HDD that has only your files on it and run Ubuntu for a few hours and see if it crashes. If not, then you have a bad HDD that is causing your problems.

Either way, back everything up so you do not lose any of your data.

[AVHATION]

Thank you, I'll try your suggestion later. I have just run Disk Utility which shows both discs to be "Good". However, it shows that my OS disk has a read error rate value of 175945830 while my data disc shows a value of only 231 ( also "Good"). Do you think that this point towards a faulty OS disc rather than the data disc?

[AVHATION]

Disconnected the data drive (the one which I transferred from old system to new) and I have had another crash. The only common factor now is Ubuntu 10.4 I believe. The OS disc SMART data is still showing "Healthy".

[AVHATION]

Another reason for suspecting Ubuntu is that when I was able to boot into WinXP there was never a problem. Unfortunately I have lost that facility when reloading Ubuntu and inadvertently overwriting the WinXP partition.

[AVHATION]

I have now reloaded again 10.04.01 from a downloaded CD i.e. not by upgrading on a brand new hard drive. The first crash has occurred after about 10 mins, while adjusting the screensaver settings. I am really disappointed that 10.4 is not a stable upgrade. Can anyone advise me how to diagnose the problem?

[AVHATION]

My problem continues. I have eliminated hardware faults and Win XP works fine. Can anyone steer me towards a method for finding out what was going on moments before each Ubuntu 10.4 crash?

[matt_symes]

Hi

After it freezes do the caps lock or scroll lock lights flash?

Kind regards

[AVHATION]

Hi Matt,
Sorry not to have responded before now; no lights appear to flash on crash. However, I think may have a workaround. I remembered that trying to set the screensaver to not operate at any time (to eliminate a variable)
always caused a crash so I have removed all reference to screensaver with Synaptic. So far all is well!

[AVHATION]

My symptoms continue. Curiously, even though I have removed all references to screensaver via Synaptic the machine still sleeps after about 10 mins. The crashing is apparently random but I do wonder if there is a way to tell what happens at the moment of the crash? Win XP continues to be fine.