Why are the hashes tied with DB_File? Are they a persistent datastore from which your program draws input? Does your program produce them, using disk instead of memory to reduce memory footprint? Will these databases grow further?

You may need to tie %hash3 to another DB_File and copy the contents key-by-key as other monks have suggested, or change your lookup code to check %hash2 and then %hash1 if the key is not found in %hash2 and elminate %hash3 entirely.

In reply to Re: memory use when merging tied hashrefs by jcb
in thread memory use when merging tied hashrefs by Anonymous Monk

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