Re: Amulet 3 times faster than Garnet

[Christopher.Young@ISL1.RI.CMU.EDU]

>From John:
>In the Garnet FAQ 
>(http://www.cs.cmu.edu/afs/cs.cmu.edu/project/garnet/garnet/FAQ),
>they answer the question, Why switch to C++, they list political & 
>technical reasons. One technical reason:
>
>* Speed: We spend 5 years and lots of effort optimizing our Lisp code,
>but it was still pretty slow on "conventional" machines.  The initial
>version of the C++ version, with similar functionality, appears to be
>about THREE TIMES FASTER than the current Lisp version without any
>tuning at all.

I wanted to add one more thing about speed. I don't know if Garnet was
using any kind of representational language in their program, but on
the project I was on, when we dump the KR language and used a much slimmer
supplement to CLOS (which actually met all our needs and was written by
this incredible lisp programmer on our project), I believe we experience
something like a *100* time performance improvement. I think he reads the list,
so he could say exactly. But it was an absolutely enormous speed improvement.
Such representation languages (such as KEE, CRL, ART, S1 and so on) were
very popular for at least a decade. But they were way too slow were more
than was needed. I'm reimplementing code which originally used such a language
from ILOG, and am getting very significant improvements in speed. SO this
needs to be taken into consideration as well.

				-- Chris.