You may be interested in DBM::Deep, which can map a memory hash to disk. It can also write files much larger than 4GB, on 64bit systems (see Large File Support).

It's also slower than a pure in memory hash, but the on-disk hash is persistent, and may perform better than a disk-swapping context.

(I'm not associated with DBM::Deep, but I used it extensively some years ago, and it saved a lot of time and trouble. So I always try to give back and suggest it where appropriate.)

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^2: what is the maximum elements storage in a Hash or an array variable by QM
in thread what is the maximum elements storage in a Hash or an array variable by Anonymous Monk

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