collision — Each hash table has a hash collision resolution strategy. Common choices include separate-chaining (SC), linear-probing (LP), double-hashing (DH)
- cache — In terms of CPU d-cache efficiency, linear probing beats quadratic-probing which beats separate-chaining. CPU cache efficiency is more relevant for very hot data content.
- clustering — Like street-parking, this can hurt linear probing. Quadratic-probing and double-hashing can cope better.
- failure — failing to locate an open slot (when available) is a problem with quadratic probing. DH, LP and SC are guaranteed safe.
- open-addressing — is alternative to chaining. It includes LP, DH etc.