analyze access.log to get bandwidth statistics, perl version

bandstats.pl

#!/usr/bin/env perl

use Date::Parse;
use Date::Format;
use List::Util qw[min max];

$\="\n";
my %slot=();
my $STEP = 60;
while ($line=<>) {
        chomp($line);
        if(not $line =~ /\[(.*?)\] ".*?" (\d*) (\d*) (\d*) (\d*)/) {
                next;
        }
        my $t = str2time($1);
        my $bytes = $4;
        my $duration = $5;
        if ($duration == 0) {
                $slot{$t} += $bytes;
                next;
        }
        $s = 1.0*$bytes/$duration;
        for(my $i = $t; $i < $t + $duration; $i +=1) {
                $slot{$i} += $s;
        }
};

$_last = 0;
$_max = 0;
for my $key (sort keys %slot) {
        my $ds = int($key / $STEP) * $STEP;
        if($ds == $_last) {
                $_max = max($_max, $slot{$key});
        } else {
                if ($_last == 0) {
                        $_last = $ds;
                        $_max = $slot{$key};
                } else {
                        @lt = localtime($_last);
                        print join("\t", strftime("%d/%b/%YT%H:%M:%S",@lt), sprintf("%f",$_max));
                        $_last = $ds;
                        $_max = $slot{$key};
                }
        }
}

if ($_last != 0) {
        @lt = localtime($_last);
        print join("\t", strftime("%d/%b/%YT%H:%M:%S",@lt), sprintf("%f",$_max));

}