Python dictionary size/entry limit?

"Martin v. Löwis" martin at
Wed Feb 25 21:19:41 CET 2009

>> On a 32-bit system, the dictionary can have up to 2**31 slots,
>> meaning that the maximum number of keys is slightly smaller
>> (about 2**30).
> Which, in practice, means that the size is limited by the available memory.

Right. Each slot takes 12 bytes, so the storage for the slots alone
would consume all available address space.

>From that point of view, you can't possibly have more than 314M slots
in a 32-bit address space (roughly 2**28).


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