Re: hashed waitqueues

Jamie Lokier (lk@tantalophile.demon.co.uk)
Wed, 16 Jan 2002 14:21:41 +0000


William Lee Irwin III wrote:
> I believe to address architectures where multiplication is prohibitively
> expensive I should do some reading to determine a set of theoretically
> sound candidates for non-multiplicative hash functions and benchmark them.
> Knuth has some general rules about design but I would rather merely test
> some already verified by someone else and use the one that benches best
> than duplicate the various historical efforts to find good hash functions.

Looking up "good hash function" on Google leads to these notable pages:

http://burtleburtle.net/bob/hash/doobs.html
A Hash Function For Hash Table Lookup - Robert Jenkins
http://burtleburtle.net/bob/hash/
Hash Functions and Block Ciphers - Robert Jenkins
http://www.concentric.net/~Ttwang/tech/inthash.htm
Integer Hash Function - Thomas Wang

The last one is interesting because it mentions the golden prime
multiplier function, and suggests good non-multipler functions instead.
(Justification: the multiplier function doesn't distribute bits evenly).

enjoy,
-- Jamie
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/