Re: [PATCH] Update jhash.h with the new version of Jenkins' hash

On Wednesday 11 February 2009 20:49:20 Jozsef Kadlecsik wrote:

Hi,

The current jhash.h implements the lookup2() hash function by Bob Jenkins. 
However, lookup2() is outdated as Bob wrote a new hash function called 
lookup3(). The new hash function

- mixes better than lookup2(): it passes the check that every input bit 
  changes every output bit 50% of the time, while lookup2() failed it.
- performs better: compiled with -O2 on Core2 Duo, lookup3() is 20-40% 
  faster than lookup2() depending on the key length.

Hi Joszef,

My concern was that it's also bigger (and we inline it).  Performance is
pretty much a wash since we so rarely hash more than a few words.

Any stats on code size changes?
Rusty.