# How should I diagnose a system freeze?

My system is freezing from time to time, what steps should I take so I can find the problem?

My system is a mac mini late 2012 i5 with 16gb of ram

• its a macmini, so the fan movement its not so obvious, I will try to see if its get hotter next time it freezes, I cant get to a terminal with ctrl + alt + f1, but spotify keeps playing for some time. – igrossiter Jul 3 '15 at 20:00
• I not doing nothing out of ordinary, just working normally, I cant see a obvious reason because it only happens sometimes. I work normally with a terminal, thunderbird, chrome, sublime text, and spotify, sometimes I have other software running like turpial, liferea, some webby apps – igrossiter Jul 3 '15 at 20:03
• spotify keep playing normally from some time, when I tried to get to tty it stopped – igrossiter Jul 3 '15 at 20:04
• I'm betting its something related to graphics driver, I messed up with it a little bit, did this: 01.org/comment/2130#comment-2130 – igrossiter Jul 3 '15 at 20:06
• I get those freezes using nvidia drivers, probably graphics related – John Guerreiro Jul 4 '15 at 9:31

## 1 Answer

First when it freezes press ctrl-alt-Fx , Fx is any of the F1 F2 F3... etc. keys.

Then there will be a terminal asking for login, Enter your user name and Password.

After that run the top command. You will get a output of a table with the most CPU exhaustive applications listed at the top of the table. From here you can know which process is the bug. If it's an application then report it to one of there websites as a bug.

You can after that restart yur computer from the terminal itself by using the command sudo shutdown +0 -r increment +0 to increase the time in minutes after which the system shuts down and remove -r to not restart the computer if you like.

• thanks for the help, as stated on the comments, in this particular case, I couldn't get to a tty using the mentioned shortcut. I had to hard reset the machine, what I want to know is where I should look for logged errors that can help to find the cause. – igrossiter Jul 5 '15 at 16:10