I need to understand how much memory is used for what in perl

Look at Devel::Size.

To the larger question, I've had some luck optimizing a large data structure by storing records using pack/unpack. I.e. rather than a hash-of-hash, I switched to hash-of-packed-array. In this case, all the data elements were just integers, so they packed down pretty well. On any particular run, I only needed some of them, so the cost of unpacking the ones I needed to access was small relative to the savings of keeping the entire data set in memory. (Plus, I could save/load the entire packed structure using Storable, too.)

-xdg

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In reply to Re: Optimizing Memory consumption by xdg
in thread Optimizing Memory consumption by PerlingTheUK

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