blokhead's analysis sounds true. When dealing with millions of values, Perl uses up all available memory.

Since you're only using integers, one method to reduce memory usage considerably is to use a string of packed integers. Tie::IntegerArray makes this transparent for you. (It's suppose to, at least. Untested.) Use it in conjunction with blokhead's change to use a reference. 

my @integer_array;
tie @integer_array, 'Tie::IntegerArray',
    bits   => 32,
    signed => 1,
    size   => 1_000_000;  # Pre-allocate this many

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By the way, why do you switch from a binary search to a linear search to find the beginning of a match?

In reply to Re: My Binary Search Perl code takes forever by ikegami
in thread My Binary Search Perl code takes forever by Anonymous Monk

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