Getting CPU utilization information

Question

How could I get the CPU utilization with time info of a process in linux? Basically I want to let my application run overnight. At the same time, I would like to monitor the CPU utilization during the period the application is run.

I tried top | grep appName >& log, it does not seem to return me anything in the log. Could someone help me with this?

Thanks.

Answer 1

vmstat and iostat can both give you periodic information of this nature; I would suggest either setting up the number of times manually, or putting a single poll into a cron job, and then redirecting the output to a file:

vmstat 20 4230 >> cpu_log_file

This would give you a snapshot of usage every 20 seconds for 24 hours.