Languages vs. machines (was Re: The need for D-scussion)

[Philip Koopman]

In article <1247 at PT.CS.CMU.EDU>, edw at IUS1.CS.CMU.EDU (Eddie Wyatt) writes:
>    It may not have been exactly 30MW but is was some outrages number like that.
> This thing was suppose to take 1/2 the power output of Yorktown.
> ...
>   Note that the machine consisted of 4096 processors.  That means that
> each processor was a 1 gigaflop processor - pretty damn impressive 
> if they can build it.
> ...
> Eddie Wyatt 				e-mail: edw at ius1.cs.cmu.edu


I believe you folks are talking about the TF-1 processor.
The head architect of that recently gave a talk at CMU, and I think
I can remember some of the details:

About 32000 processors, total floating point computation speed 1 Tflops.
Every processor has 2 computation elements that are checked for
consistency to spot errors.  Any inconsistency takes the element off-line.

Total power about 3.5 MW.  Yes, powering the system up is interesting
(so is cooling).
Implementation is CMOS.  That means that if the system clock dies
at the full operating speed of something like 20 MHz or so, the
dI/dt current change melts the power lines and blows up the
substation (and maybe the East Coast power grid???? *grin*)
They're working on redundant/fail-safe clock distribution.

The thing has got a LOT of packet switching capability (more
than all the telephone switching capability in the world) to
get the processors to communicate.

An interesting and ambitious architecture!


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~  Phil Koopman             5551 Beacon St.             ~
~                           Pittsburgh, PA  15217       ~
~  koopman at faraday.ece.cmu.edu   (preferred address)    ~ 
~  koopman at a.gp.cs.cmu.edu                              ~
~                                                       ~
~  Disclaimer: I'm a PhD student at CMU, and I do some  ~
~              work for WISC Technologies.              ~
~              (No one listens to me anyway!)           ~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~