Re: Scheme style auto-resizing hashtable

[Maciej Stachowiak <mstachow@mit.edu>]

jglascoe@jay.giss.nasa.gov writes:
> more timing tests reveal:
> 
> python dictionaries (as ported to Guile):
>    3% faster than the Guile hash.  The catch is, you must choose the
>    vector size very carefully to get this kind of performance from the
>    (non-resizable) hashes.
> 
> my hashtable things:
>    3 % slower than the Guile hash (don't you love symmetry?  ;)
>    5 % slower if I use my own hashing function (I've found the current
>    Guile hasher to be inadequate for my needs).

Hmm, if the difference is that small, maybe it would help to keep the
auxiliary data in a vector instead of an alist?

Also: what limitations are you finding in the Guile hash functions?
Just the fact that they need a prime range to work well?


>  Would anyone knowledgeable about bit twiddling be willing to write
> a Guile hasher that doesn't mod out by a given number?

Time to whip out _The_Art_of_Programming_ ...

 - Maciej Stachowiak