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From: rphroy!rcsdjm!dmcmilla@cfctech.cfc.com (Don McMillan CS 50)
Newsgroups: comp.parallel
Subject: Re: Acceptable efficiency factors
Message-ID: <9547@hubcap.clemson.edu>
Date: 3 Jul 90 13:08:37 GMT
Sender: fpst@hubcap.clemson.edu
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Approved: parallel@hubcap.clemson.edu

In article <9508@hubcap.clemson.edu>, xxremak@csduts1.lerc.nasa.gov
(David A. Remaklus) writes:
|> 
|> It is our contention that it is necessary to achieve an efficiency factor
|> of at least 50% before the particular implementation of the code can be
|> considered appropriate for execution on that parallel processor system.
|> What are your opinions on this matter?  Are there any published papers
|> that deal with this subject?
|> 

You're in good company.  See "Speedup Versus Efficiency in Parallel
Systems", IEEE Trans on Computers, vol 38. no 3, March, 1989.

Basically, the authors define a method for determining the "average
parallelism" of a given algorithm, and thence to selecting the most 
appropriate number of processors such that at least 50% of the maximimum
possible speedup is attained, with at least 50% efficiency.

Don McMillan           __  .   .   Phone: (313) 986-1436
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