Path: utzoo!utgpu!watmath!att!pacbell!ames!indri!aplcen!jhunix!ins_atge
From: ins_atge@jhunix.HCF.JHU.EDU (Thomas G Edwards)
Newsgroups: comp.arch
Subject: Re: New Bell Award
Summary: CM2 Use
Message-ID: <2238@jhunix.HCF.JHU.EDU>
Date: 8 Aug 89 20:36:04 GMT
References: <107900005@iuvax> <8953@june.cs.washington.edu>
Reply-To: ins_atge@jhunix.UUCP (Thomas G Edwards)
Organization: The Johns Hopkins University - HCF
Lines: 25

In article <8953@june.cs.washington.edu> david@tera.com (David Callahan) writes:
!>>(from the benchmark contest)
!>>The number of processors is defined as the number of simultaneous
!>>program execution streams, i.e., in effect the number of  program
!>>counters in simultaneous operation.  For example the Cray Y-MP in
!>>operation today has 8 processors and the number is  projected  to
!>>grow  to 16 and 64 for the Cray 3 and 4.  Similarly, the Thinking
!>>Machines Corp. CM2 has up to 4 processors each with 16K  process-
!>>ing elements or is a uniprocessor with 64K processing elements.

!>(Aside: isn't the CM2 a single stream machine? I'd never heard that
!>the 4 quadrants could be run independently.)

Yes, depending on your installation, the CM can be split up into several
segments.  We have a 16K CM2 which can be attached to as 16K processors
or 2 users @ 8K processors (we also have an 8K CM2 which can be used as
all 8K or two users @ 4K...).

And just because every processor gets the same instruction feed, one must not
think that every processor is "doing the same thing." Each CM processor
can hold an index to an array located in that processor, so with the
right software, the CM could become a MIMD machine.  

-Thomas Edwards
 tedwards@cmsun.nrl.navy.mil