🚀 go-pugleaf

  To: comp.lang.clos@cis.ohio-state.edu
  Date: Wed, 26 Aug 1992 09:56:27 GMT
  Organization: The Ohio State University Department of Computer and Information Science
  From: cb@maths.bath.ac.uk
  Sender: commonloops-request@cis.ohio-state.edu
  References: <17dmf7INNb4l@early-bird.think.com>
  Subject: Beginner's Question - CLOS
  
  >How much slower is that than the C++ or C version?  Timings are meaningless
  >without some basis for comparison.
  
  Well, it's sort of like comparing apples and oranges, because
  the C version basically hard codes the Petri net and has
  lots of direct array accesses (like Place[3].count). I think the
  C compiler produces good code for direct array accesses.  However, the
  C version  has no object-oriented features--mine does.
  
  Also, the lisp version that I wrote handles marking dependent firing
  rates which the C implementor admits would slow down his
  system--though I don't know by how much.  Anyways, mine running in CMU
  Common Lisp on a Sparcstation ELC executes about 400 transitions a
  second (it's slower running in Eulisp on a Stardent).  The C version running
  on a Sparcstation 2 (I don't know how much faster that is than an ELC) executes
  about 20,000 transitions a second.  Note I was running a smaller petri net
  simulation and it had marking dependent firing rates.  That's why I just
  said that the Lisp version  is way, way, slower.
  
It sounds like you don't need C++ as much as a Petri net compiler that
takes your nice object oriented specification and spits out fast code, like
a big PROG, for example.

k