hash function for mac needed

[Rich Salz]

In <1991Jun19.161959.13677 at zoo.toronto.edu> henry at zoo.toronto.edu (Henry Spencer) writes:
|In fact, when I originally did the hashed newsgroup-lookup code in C News
|expire, a quick investigation did not reveal any hashing function which
|had overall performance much better than simply using the length of the
|string!  (The newsgroup list has grown so much that this decision is in
|need of revision, mind you.)

I think you'll want to re-check.  The distributions are real uneven -- there
are more than 40 newsgroups of length 10, for example, so you have to resolve
lots of conflicts, and if you don't put a secondary hash, that means lots of
strcmp's.  Of course, the design is very dependant on the newsgroup that a
site receives and the distribution of articles within those sites.

I use Chris Torek's hash function (amazingly good distribution and amazingly
cheap to calculate) with a table size of 128 and sort the conflicts based on
the highest article number.  It seems to give the biggest win for the biggest
number of systems.
	/r$
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