No values are required for lookup purposes. And the length of the keys makes surprisingly little difference to the size of the hash.
For example: For a hash with 11,881,376 keys:
- From 5-bytes keys (the minimum required) to 14-bytes keys, the memory required remains almost static at 1.7GB.
- From 15-bytes through 29-bytes, it goes to 1.9 GB.
- From 30-bytes through 46-bytes, it goes to 2.1 GB.
- from 47-bytes .... , it goes to 2.3 GB.
So if I have 11,881,376 keys with an average key size of say 250 bytes it would only be 2.3 GB? Same with 400 bytes? Or 500 bytes?