You can use DB to process the data but if you want to do it in Perl, below is some pseudo-code for processing the log data (assuming raw data is saved in a file):

open INF infile for reading or die cannot read file
define data hash
while read line from file
    chomp line
    next if line start with '#' or empty line
    split line on ',' and save in @tmp
    $data->{$tmp[1]}{$tmp[4]}{$tmp[2]} += $tmp[3];
end while

print "IP\tWrite/Read\tTotal\tFileName\n\n"

foreach ip ( sort keys data )
   foreach file ( keys data->{ip} )
       foreach rw ( keys data->{ip}{file}
           total = data->{ip}{file}{rw}
           print "$ip\t$rw\ttotal\tfile\n"
       end foreach rw
   end foreach file
end foreach ip
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Assuming the 2 numbers on 'another.file' is a typo, otherwise you need to do some more processing with it in the while loop