Well, doesn't everyone have an S390?

Assuming that all his keys are unique, you are right, the OP will need to use some sort of disk based storage--he probably doesn't have enought RAM. Perhaps an SQL database (SQLite anyone) or a dbm file would do the trick.

Any reason why tying each hash to a DB_File would be a bad idea? The largest datasets I've had to deal with have only been in few 10s of megabytes in size. So, is DB_File up to the task?

Would you care to offer a suggestion?

Edit: Upon reviewing the OP's code, it looks like he is keeping both hashes in RAM at the same time (at least the worst case memory consumption for my code and the OPs is the same). If his code runs to completion as posted, so will mine. I also noted your suggestion to try DB_File, and so struck my request for suggestions.


TGI says moo

In reply to Re^3: Perl Code Runs Extremely Slow by TGI
in thread Perl Code Runs Extremely Slow by garbage777

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