Whenever you want a fast lookup, try to use a hash. This will only work if your elements exist as single lines instead of actual substring matches. Also note that if $strfile contains regex meta characters (like *, . or +, or []) your code will not work as you might think.

Using a hash would result in:

my %lookup = map { $_ => 1 } @arraytocompare;

foreach my $strfile (@tempfiles) {
    if( $lookup{ $strfile } ) {
        push (@newarray, $strfile); 
    };
};

[download]

But I really, really doubt that searching through 8000 array entries will slow your program down that much. Are you certain that this is where your performance bottleneck is?

In reply to Re: improve performance by Corion
in thread improve performance by swissknife

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