🚀 go-pugleaf

In article <30115@sun.uucp> ram%shukra@Sun.COM (Renu Raman, Sun Microsystems) writes:
>In article <454@trwspf.TRW.COM>, thomsen@trwspf.TRW.COM (Mark Thomsen) writes:
...
>> I would like any references or descriptions on Prolog machines that you guys
>> know of.  I will submit a summary of received data in a few weeks.  Thanks!
...
>     If you talk of prolog hardware - the fastest available today is from
>     UCB called PLM. (Yeah! they are a few orders of magnitude faster than
>     Japanese PSI - How about a university project out-performing a
>     national project)  Al. Despain has been instrumental in its development
>     and so are Dobry, Srini, P. Van Roy  & co.  The First Hardware was
>     available thru Xenologic [X-1] which hooks onto a Sun VME backplane was
>     performing at 300K lips and the new CMOS version is > 500K (maybe 800K.
>     I think the PSI barely reaches 3 figures).  Apparently the new CMOS version
>     (I don't know how true this is) is available as a MOSIS tape and
>     you can probably license it and fabricate it.  There is a pretty
>     efficient compiler that goes along with it (Written by Van Roy).
>     I guess the new PLM hardware hooks onto an NCR (as it was developed
>     thru an NCR grant).
...
>     Hope this helps.  Info given here are from sketchy info that I
>     have gathered.  If there is any wrong info here - please correct me
>     [I am sure Despain & Co. read this newsgroup].
>
>---------------------
>   Renu Raman				ARPA:ram@sun.com
>   Sun Microsystems			UUCP:{ucbvax,seismo,hplabs}!sun!ram
>   M/S 5-40, 2500 Garcia Avenue,
>   Mt. View,  CA 94043

Thanks for the kind words.  Let me give some background on the Aquarius 
project here at Berkeley.  The group has built several Prolog machines to 
date, beginning with an NCR 9300 based system.  Prolog programs were compiled 
to WAM (Warren Abstract Machine) and then to microcode.  With a cycle time 
of 150 ns., this system achieved 53 KLIPS for determinate concat in 1985.

The next machine, the PLM, was a TTL implementation of the WAM with some
local improvements, see [Dobry87].  The PLM was simulated to run at 400 KLIPS 
for determinate concat, based on a 100 ns. cycle.

Another project implemented the WAM instruction set in microcode on a VAX 8600.
This machine, with an 80 ns. cycle, reached 108 KLIPS on determinate concat.

The most recent machine (chip actually) is the VLSI PLM, being fabricated 
right now.  This is a 200K equivalent transistor, 1.4 micron CMOS implement-
ation of an extended PLM.  With a cycle time of 100 ns. this chip has been 
simulated at 416 KLIPS for determinate concat and 98 KLIPS for Warren's Chat 
program.

The Prolog compiler used for most of this research was written by Peter Van 
Roy [VanRoy85], and is available directly from him.  He can be reached via 
email at vanroy@ji.berkeley.edu.

Unfortunately, the VLSI PLM is not available as a MOSIS tape as Renu's
message indicated.  The chip was funded in part by NCR and they are 
fabricating it for us and for their own use.

Our focus has shifted away from single processor systems; current research 
centers around parallel execution Prolog machines.  For some results from 
recent work in this area, see [Fagin87].  Altogether, more than 50 papers 
and reports have been produced by the Aquarius project.  If anyone would 
like a list of the publications, please send electronic mail to Kathleen 
Nimr (nimr@ji.berkeley.edu).  Most of these publications are still available 
from her.

As for commercial products, Xenologic licensed the PLM design from the
university and has designed an improved version, called the X-1.  This is a 
set of 2 VME boards which plug into a Sun workstation and function as a 
coprocessor.  I don't have exact performance figures for their machine, but 
have been told that they are better than the PLM.  If you would like more
information you can contact Xenologic at 39899 Balentine Dr., Suite 145, 
Newark, CA 94560.  Their phone number is (415) 656-0708.

Hope this helps, if you would like more information or have any questions 
please send us mail,

Mike (and the rest of the Aquarius group)

carlton@ji.berkeley.edu  or      
...!ucbvax!ji!carlton  	        
			
References:
Dobry, T., "A High Performance Architecture for Prolog", Ph.D Dissertation, 
       UCB, May 1987

Fagin, B., Despain, A., "Performance Studies of a Parallel Prolog 
       Architecture", 14th ICSA, June 1987

Van Roy, P., "A Prolog Compiler for the PLM", UCB/CSD Report No. 84/203, 
       November 1984 

Disclaimer:  I have nothing to do with Xenologic (other than wanting my
own X-1 for the Sun in my office!).  However, some members of our research 
group do have connections with Xenologic.  This should not be construed as 
an advertisement for Xenologic.