8

This thread shows how to measure the time it takes to run a script. In my case, I am interested in measuring time between two points within a script. Here is an example of how I would like to use this:

start_measuring_time
Line 1
Line 2
..
Line N
stop_measuring_time
show_elapsed_time

I would like the displayed time to be human readable (secs, min, hours, days, etc.), if possible. Any ideas how to do this?

Community
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Amelio Vazquez-Reina
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3 Answers3

12

You could just use time:

time (
Line 1
Line 2
..
Line N
)

I think the output of time is human readable as is, but if your script is going to measure in days, etc., then check out man time for formatting options for the output.

frabjous
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  • Thanks @frabjous! I think I will accept @enzotib's answer because it allows me to measure time in general control flows (i.e. not just in linear flows). – Amelio Vazquez-Reina Aug 12 '11 at 19:05
7

You can use date util:

#!/bin/bash

start_measuring_time() {
  read s1 s2 < <(date +'%s %N')
}

stop_measuring_time() {
  read e1 e2 < <(date +'%s %N')
}

show_elapsed_time() {
  echo "$((e1-s1)) seconds, $((e2-s2)) nanoseconds"
}

start_measuring_time
sleep 2
stop_measuring_time
show_elapsed_time
enzotib
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  • This will produce errors: the beginning and ending times need to be interpreted as seconds + nanoseconds **together**, not separately - you can get things like negative values otherwise. – rozcietrzewiacz Sep 01 '11 at 11:23
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    See my answer to [this question](http://unix.stackexchange.com/questions/19866/linux-patches-related-to-time-measurement-accuracy/19899#19899) for a way to solve this. – rozcietrzewiacz Sep 01 '11 at 11:56
  • I had to downvote since its not comletely correct answer, correct it gives negative values at times but in your question why aren't you putting echo before `Tend-Tstart` and after `$(` – munish May 05 '16 at 06:00
1

Sample to try timerscript.sh:

#!/bin/bash

#timing in minutes with %m
start=`date +%m`
echo 'Start:' $start
#do something e.g. wait for 1.30 minutes 
sleep 90

`end=`date +%m`
echo 'End: '$end
echo 'runtime: '$runtime
Jorduino
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