Variables in perl take up at least pointer and two native ints (for just an undef) plus at least the size of the data being stored for ints and double-precision floats. So in this case you've got a pointer, two ints, and a double, which will snag 20 bytes per array element, not counting the array overhead itself. So you've 16M elements, times 20, plus array overhead.

Perl, as has been pointed out, is not stingy with memory. There are ways around it, but none used yet. (Perl 6 has provisions to be much stingier, but it's not done yet)

This seems to be a common thing. I may well throw together a Stingy::Array module or something to get better packing.

In reply to Re: why does this array take up so much memory? by Elian
in thread why does this array take up so much memory? by Anonymous Monk

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