On 3/22/12 1:18 PM, H. S. Teoh wrote:
Alright, so after some benchmarking, I found that the above custom hash
function works best for *short* (3 to 10 character) randomized
alphabetic strings (I assumed alphabetic to be the typical use case of
strings). It's faster than SuperFastHash, and even has better
distribution properties, probably because SuperFastHash is tuned for
arbitrary binary data of arbitrary length, whereas the custom function
is tuned for short string-like data.
With longer strings, SuperFastHash beats the custom algorithm, and
distribution properties are approximately the same.
So I'm still on the fence about which algorithm is better. I can see why
the custom hash was adopted for strings, since your typical AA tends to
have short alphabetic keys, and something like SuperFastHash is probably
overkill. But for longer keys, SuperFastHash is better.
Note that you can switch the actual algorithm depending on string length.
Andrei
