Abesnt a lot of real data it is hard to test. I do, however have a few suggestions:
  1. Try to profile the code, e.g. using Devel::DProf to see where the time is used.
  2. Consider the loop: 
    foreach $ip ( sort { $by_ips{$a} <=> $by_ips{$b} } keys %by_ips ) {
...
}

    [download]
    You might save time dividing it up into the three lists of <499, <=599, >599 first if the list is large and the sort slow. 
  3. (@data) = grep(!/received from internet:/, @in);
(@data) = grep(!/Error-Handler/, @data) if ( grep(/Error-Handler/, @da
+ta) && 
+$data[1] );

    [download]
    The second assignment appears to override the first...
HTH, --traveler

In reply to Re: The need for speed by traveler
in thread The need for speed by l2kashe

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