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From: wilson@carcoar.Stanford.EDU (Paul Wilson)
Newsgroups: comp.parallel
Subject: Re: Optimistic / Speculative Programming
Keywords: Optimistic computation, parallelism, PARATRAN
Message-ID: <6714@hubcap.clemson.edu>
Date: 9 Oct 89 18:22:20 GMT
Sender: fpst@hubcap.clemson.edu
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I just came across another one: "An Execution Model for Distributed
Object-Oriented Computation,"  by Edward H. Bensley, Thomas J. Brando,
and Myra Jean Prelle of the MITRE Corporation, in the OOPSLA '88
proceedings (Special issue of SIGPLAN Notices, vol 23, no 11, Nov. 88,
pp. 316-322.

   My first impression is that this looks a whole lot like Morry Katz'
Paratran system.  It uses the program call graph to generate virtual
timestamps using an infinite-precision ("littlenums?") subdivision
mechanism.

   Anybody know both of these systems and care to comment?  Has anybody
heard from these people since and know what they're up to now?


   By the way, in my MS thesis, I described (but haven't implemented)
a system that supports the same abstraction as Jonathan Smith's
"Multiple Worlds," only I call it "Alternate Universes."  My implementation
ideas are quite different, though, supporting finer-grained parallelism
and being less sensitive to poor locality.  I also discuss garbage
collection across multiple worlds/universes/whatevers.  On the other
hand, mine incurs a certain amount of continual overhead on stock
hardware.
   
   -- Paul

Paul R. Wilson                         
Software Systems Laboratory               lab ph.: (312) 996-9216
U. of Illin. at C. EECS Dept. (M/C 154)   wilson@carcoar.stanford.edu
Box 4348   Chicago,IL 60680