How to get/check which parts/lines in bash script takes the most execution time?

Question

I have a bash script which is very long and performs some stuff in the background (without producing any output).

I would like to get to know which lines/parts take the most of execution time.

Can I achieve with some kind of tool/function/linux builtin ?

See http://stackoverflow.com/questions/5014823/how-to-profile-a-bash-shell-script — Stefan, Apr 16 '13 at 12:05
Somehow it won't help. On redhat 6 I do not have `/etc/bash.bashrc` only `/etc/bashrc`. Even though if I use it instead of the former I am not getting the trace. — Patryk, Apr 16 '13 at 12:15
You have to put the lines in the bash script you want to profile. — Stefan, Apr 16 '13 at 12:24

score 0 · Answer 1 · answered Apr 16 '13 at 13:12

I can think of two approaches here.

1) Log the time each command or function starts at and output to a log file

# echo "$(date) : Started function_x" >> $LOGFILE

2) Figure out the number of seconds each function/task takes and log that.

startTime=$(date +%s)
longRunningFunction
endTime=$(date +%s)
echo "longRunningFunction took $(expr $endTime - $startTime) seconds" >> $LOGFILE

score -1 · Answer 2 · answered Apr 16 '13 at 13:22

-1

When I've had to do this in the past I've used this kind of format: ( time echo "hello" ) 2>>output.txt

Do this for every line in your script to time each one.

answered Apr 16 '13 at 13:22

James

2 Answers2