I have 12.04 and it works great. But I've noticed intermittent crashes that freeze the screen. They have been happening more frequently on this version of linux than any I have ever used.
(I ran a memory test, without problem). 12.04 64 bit on a somewhat old amd system with Radeon HD 2600XT card.
I have two issues:
1)how do I escape when I see that the crash is occurring or will be about to occur?
2)how do I gather clues for figuring out what is causing the problems?
Let me give some information about what I already know:
- crashes when using Dropbox for the first time. (This is now fixed and no longer a problem).
- crashed when loading music libraries in Amarok/RhythmBox for the first (and maybe the second time).
- crashed multiple times (sometimes suddenly and unexpectedly) when using Firefox, often when it's using a lot of memory. (I have 4 gigs total, so sometimes the memory usage is very high).
- crashed when loading video. (more than once)
For the audio/video applications I was trying to access NTFS partitions which were unmounted by default. I suspect that the system freezing might be a result of trying to play files which are inaccessible because the partition was unmounted. However, I just set fstab so that this Windows drive will always mounted, so I should know if this has anything to do with it.
Looking here, https://wiki.ubuntu.com/X/FixingCrashes I see two other potential issues: proprietary modules and overheating. I have loaded the fglrx proprietary drivers for Radeon, and honestly I don't remember if they were loaded until today. I guess I don't understand why a potential videocard problem could cause the whole keyboard to lock. Often I am unable to open System Monitor, and ‘Ctrl + Alt + Backspace‘ doesn't do anything in Ubuntu 12.04. If I do 'Alt + SysRq + K’ it does something, but I'm not sure it's good. Instead, I see vertical red lines all over the screen and no apparent way to escape -- not even TTY. (Is this expected behavior?).
I'd assume that I'd be able to drop to a console. Many times the system locks up before I had a chance, and besides I have two problems (dont' laugh!)
1. Even if I were able to open up a console in a separate session, I'm not sure what application I'd want to kill. What is the name of the windows manager app in Ubuntu 12.04 which I'd want to be killing or restarting (I don't see gnome, dgm or kde; is it nautilus or unity (which one?)
2. During normal use, I can Ctl_Alt F1 to open TTY 1. My login can work here, and I see that if I create a dummy file, it is owned by root. But the command line shows a $, not a #, Why is that?
Anyway, thanks for your help.