If you started a long-running process and want to know how long it has been “on the run” so to speak, you can use the
-eo switch on
ps to specify you want the elapsed time like so:
ps -eo pid,cmd,etime
This will yield something like:
112 [aws/0] 2-10:27:00 114 [aws/1] 2-10:27:00 115 [aws/2] 2-10:27:00 123 [aws/3] 2-10:27:00 ...
Which means that process
aws has been running for 2 days, 10 hours and 27 minutes.
You can of course pipe the result to grep:
ps -eo pid,cmd,etime | grep aws