#!/usr/bin/perl -w
use strict;

use Time::HiRes qw[ time ];

# OP: "I have a perl script that I need to run 1000 times and for each run 
#      I need to store how much time it took to run... "
# using foo_a.pl, execute this from foo_a's dir
# Timings of foo_a.pl are NOT precise because they include the time 
# to execute the calculations here.

my $begin = time;
for my $arg( 1..1000 ) {
	my $start = time;
	system "perl foo_a.pl $arg";
	my $duration = (time - $start);
    print "\n\t\$arg: $arg, \t\$start: $start, \t\$duration: $duration\n";
	$start = time;
}

print "$begin" . time . "\n";
exit;