Path: utzoo!attcan!uunet!mcvax!unido!ecrcvax!bruno
From: bruno@ecrcvax.UUCP (Bruno Poterie)
Newsgroups: comp.lang.prolog
Subject: Re: "A Note on the Speed of Prolog"
Keywords: prolog execution speed
Message-ID: <563@ecrcvax.UUCP>
Date: 18 Jul 88 08:13:10 GMT
References: <6251@megaron.arizona.edu>
Reply-To: bruno@ecrcvax.UUCP (Bruno Poterie)
Organization: ECRC, Munich 81, West Germany
Lines: 28

In article <6251@megaron.arizona.edu> debray@arizona.edu (Saumya Debray) writes:
>
>The current (August 88) issue of ACM SIGPLAN Notices has an article
>"A Note on the Speed of Prolog", by J. Paakki, that's
>interesting.  The author reports on an experiment comparing the
>speeds of compilers, written in Pascal and Prolog, for the
>...
>available), this seems to suggest that using a "state-of-the-art"
>Prolog system, one could actually have a Prolog version of the
>compiler that was faster than the Pascal version.
>-- 
>Saumya Debray		CS Department, University of Arizona, Tucson
>
I do not believe that we can apply the speed-up factor for a compiler
application. Remember that this "10 to 50 times" is the speed-up of the
pure "Prolog Engine" part of the system, while the builts-in are in both
case written in the implementation language, therefore remaining identical
in speed. In fact C-Prolog may be even better because the builts-in are
integrated into the emulator loop instaed of beeing linked functions with
call overhad. From our own experiences here, writting a (Prolog to WAM-like)
compiler in C-Prolog and then compiling it did not increased very much speed,
because most of the time was spent in i/o and database access for tables.
Although me must take in account the fact that our compiler was a prototype
system, we got increases from 1.6 to less than 2.5, depending heavily on the
size of the source and therefore on the quantity of i/o and database size
and accesses numbers.

--Bruno Poterie