G'day gopikavi,

Welcome to the Monastery.

I see ++huck has pointed out your indexing error and usage of a hash. Here's an alternative method for capturing the data:

#!/usr/bin/env perl -l

use strict;
use warnings;

my %slot;
my $re = qr{([a-z]{3}).*?(\d+)/(\d+)};

while (<DATA>) {
    if (/$re/) {
        $slot{$1}{used} += $2;
        $slot{$1}{free} += $3;
    }
}

print "$_: @{$slot{$_}}{qw{used free}}" for sort keys %slot;

__DATA__

{asf192lin1 C 0/8 0 0 0 4503 16 2922 44316 1}
{asf256lin10 + 2/16 15 0 0 4641 16 2926 194108 0}
{cad192lin1 C 0/12 2 0 0 1432 12 3397 179605 0}
{cas256lin1 C 0/12 50 0 56 3992 12 3397 165099 0}
{cas192lin11 C 0/12 50 0 56 3992 12 3397 165099 0}


{dsf192lin6 + 0/16 0 0 0 4751 16 2930 179123 0}
[download]

Output:

asf: 2 24
cad: 0 12
cas: 0 24
dsf: 0 16
[download]