Re: poor m4 hash performance

[Ben Pfaff]

address@hidden (Eric Blake) writes:

> However, it seems like there are two things we can improve.  First, should
> autom4te experiment with changing the default hash size, using the
> -H option?  By default, m4 1.4.4 uses a 509 bucket hash table, with no
> dynamic growth.  Without a larger table, configure scripts are so complex
> that you are generating loads of collisions and extra time spent comparing
> strings.  But what size would be the best trade of memory for speed, and
> how do we judge how complex the configure script is?

Is there a good reason why m4 should not use a hash table that
grows dynamically?  It is easier to deal with software that can
figure out parameters on its own rather than having to be told.
-- 
Ben Pfaff 
email: address@hidden
web: http://benpfaff.org