Using Time Command to Benchmark

halfpower · 03-06-2011, 01:51 PM

I am trying to use the time command to measure the execution time of a small program. The problem is that the command has three outputs. They look like this:

Code:

$ time ./a.out
real	0m51.935s
user	0m51.060s
sys	0m0.040s

Should the execution time be the sum of the user and the sys time? sys time is really small. Can it be ignored?

zWaR · 03-06-2011, 05:14 PM

A little googling around can produce a lot of info on that... e.g.: http://linux.byexamples.com/archives...enchmark-tool/

halfpower · 03-06-2011, 09:02 PM

I did see the page. What I'm not sure about is the significance of sys time. What causes a program to use sys time?