Top

From Waisman Brain Imaging Wiki

'top' is a UNIX tool that shows what's running on a computer, in order of how much processing power each job is using up. To run it, just type

top

and after a few seconds (or several, if the computer is very busy), it will display a list of the most resource-chomping programs currently running (plus some other useful info, like the name of the user running that monster SAS job which currently taking up 97% of the CPU). After a few more seconds, 'top' will refresh the list. To quit, press the "q" key.

If you're a system administrator, you can press the "k" key to kill one of the listed jobs and free things up for your monster SAS job. But you're not a system administrator, and this is a good example of why you're not.

One thing that 'top' doesn't display is how much network bandwidth a job is using up. This would be useful to know, since your computer can slow down when the network gets overloaded. There is a similar command called 'ntop' which does indeed display network usage instead of CPU usage. But it is not very stable, uses a lot of CPU time, and only displays the network usage for the computer it is running on, not for every computer in the lab.

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