You do want to use Benchmark. Check out the method timediff.

like this: 

use Benchmark;

my $start1 = Benchmark->new();

##Code you want to profile

my $end1 = Benchmark->new();
my $diff1 = timediff($end1, $start1);
print "Section 1: ", timestr($diff1);

my $start2 = Benchmark->new();

##Next section of code you want to profile

my $end2 = Benchmark->new();
my $diff2 = timediff($end2, $start2);
print "Section 2: ", timestr($diff2);

[download]
Update: slightly better using HoH. 
use Benchmark;

my ($fn1,$fn2) = @ARGV;

my %benchs;

my $cnt = 0;
$benchs{section_1}{start} = Benchmark->new();
open(FH,$fn1) or die();
while (my $line1 = <FH>) {
    $cnt++ if ($line1 =~ /\./); 
}
print "$cnt\n";
close FH;
$benchs{section_1}{end} = Benchmark->new();

$cnt = 0;


$benchs{section_2}{start} = Benchmark->new();
open(FH,$fn2) or die();
while (my $line2 = <FH>) {
    $cnt++ if ($line2 =~ /\./); 
}
print "$cnt\n";
close FH;
$benchs{section_2}{end} = Benchmark->new();



foreach my $b (keys %benchs) {
    print "$b: " ,timestr(timediff($benchs{$b}{end}, $benchs{$b}{start
+})),"\n";
}

[download]


grep
Mynd you, mønk bites Kan be pretti nasti...

In reply to Re: performance profiling by grep
in thread performance profiling by thedoe

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