And to further expand on ignatz, you can switch to something like DB_File (which is in core perl) or BerkeleyDB and not have to change your code much. You keep your hash - it's just tied to a database. I've used BerkeleyDB to good effect for working with large datasets that didn't fit into memory.

Update: you'll probably also want to use something to store your structures as well: Storeable, MLDBM, FreezeThaw, Data::Dumper, etc. You can't just store raw structures but the idea is the same.

__SIG__
printf "You are here %08x\n", unpack "L!", unpack "P4", pack "L!", B::
+svref_2object(sub{})->OUTSIDE
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