time command

time, One of the Most Useful Linux Commands

If you run or write a lot of software run on the command line from time to time you probably want to know how long something you ran took to run. ¬†What’s great about the time command is all you need to do to use it is throw it in front of whatever you were already running.

Here are a few examples

How long does it take to download a url
time curl -s 'http://www.google.com' > /dev/null

real 0m0.242s
user 0m0.037s
sys 0m0.017s


Time your python script runtime
time python your_cool_script.py

real 0m5.139s
user 0m0.134s
sys 0m0.323s

real – the wall clock time it took a process to complete, or how long it took to run.
user – number of cpu seconds the process used directly.
sys – number of cpu seconds the kernel used on behalf of the process.


Leave a Reply

Your email address will not be published. Required fields are marked *