What to do when a linux desktop freezes?

Question

I'm a Windows guy, dual booted recently, and now I'm using Linux Mint 12

When a Windows desktop freezes I refresh, or if I am using a program I use alt + F4 to exit the program or I can use ctrl + alt + delete and this command will allow me to fix the Windows desktop by seeing what program is not responding and so on.

Mint freezes fewer times than my xp, but when it does, I don't know what to do, I just shut down the pc and restart it.

So is there a command to fix Linux when it freezes?

Answer 1

You can try Ctrl+Alt+* to kill the front process (Screen locking programs on Xorg 1.11) or Ctrl+Alt+F1 to open a terminal, launch a command like ps or top to see running processes and launch kill on not responding process.

Answer 2

If all else fails, you Raise The Elephant. Essentially, there are special Alt+SysRq+? key sequences that the Linux kernel handles special.

If your Linux box freezes and simply won't yield to any other key-commands, you should definitely try one particular key sequence before a hard reboot.

The key sequence is popularly remembered with the nemonic:

Raising Elephants Is So Utterly Boring

Alt+SysRq+R switch keyboard to 'raw' mode

Alt+SysRq+E send SIGTERM (termination) signal to all processes except mother init

Alt+SysRq+I send SIGKILL signal to all processes, a little more aggressive

Alt+SysRq+S sync all filesystems to prevent data loss

Alt+SysRq+U remount filesytems as read-only

Alt+SysRq+B forcefully reboot

http://en.wikipedia.org/wiki/Magic_SysRq_key

Answer 3

In most distros pressing Ctrl+Alt+Backspace kills the X11 (graphic) interface and restarts it. Unfortunately some recent, supposedly "user friendly" distros deactivated this very useful shortcut for some unfathomable reason. I don't know if Mint is so "user friendly" but you have nothing to lose trying it :)

Answer 4

Another suggestion if you are using Gnome3 (I think the default Mint installation uses something similar), you can use CTRL+F2 then press R and hit return. I use this often and it works. It basically restarts the GUI. Even if you don't see anything on the screen (e.g., it is frozen) you should do that and it will restart the GUI.

Answer 5

On laptops you might need to press CtrlFnF1 to open terminal, what I do is type reboot now to restart from terminal.

To go back to the GUI from terminal on my laptop (HP G56) I have to CtrlFnF8 (apparently it could also be CtrlFnF7) and you should be back to graphical interface.

Also check http://community.linuxmint.com/tutorial/view/244

Stopping & Starting

• shutdown -h now – Shutdown the system now and do not reboot
• halt – Stop all processes - same as above
• shutdown -r 5 – Shutdown the system in 5 minutes and reboot
• shutdown -r now – Shutdown the system now and reboot
• reboot – Stop all processes and then reboot - same as above
• startx – Start the X system

Answer 6

Since Linux Mint is Ubuntu based, in Ubuntu 11.10 (I know, its Unite, never tryed in Mint) Ctrl+Alt+F7 gave me the best result in solving this kind of problem.

With a single shot!-)

Answer 7

Instead of Ctrl+F2, press Alt+F2. Then it works fine.

Answer 8

Besides what was already mentionned, I also use those tricks:

• If by any chance the unresponsive program was started in a terminal, I would try a Ctrl+D or Ctrl+C. If nothing happens I'd try a Ctrl+Z followed by a ruthless kill.

• If I knew the responsible program, I would open a terminal and use killall. (E.g., killall firefox)

• Alternatively, under Gnome, I would launch run command and invoke xkill, which allows you to kill a program by simply clicking on a window it owns.

• Finally, just in case my keyboard melts, I have a System Monitor applet (also under Gnome) which will pop up the gnome-system-monitor when clicked. From there, I can kill any process I own using only my mouse.