🚀 go-pugleaf

In article <23379@winchester.mips.COM>, mash@mips.COM (John Mashey) writes:
> In article <337@venus.iotek.UUCP> garyb@iotek.UUCP (Gary R. Burrell) writes:
> 
> >IEEE Micro December 1988
> >
> >	A Special Issue on DSP processors, contains detailed articles
> >on the TMS320C30, DSP32c and DSP96002.  These are fairly good articles
> >about the various DSP processors.  The only part of the issue I really
> >question is the editors afterword in which they come up with some
> >amazing figures for Linpack ratings of the TMS320C30 (20 MFLOPS) and
> >DSP96000 (30 MFLOPS).  I question these ratings as most supercomputers
> >only get about 1/10 of there peak performance rating on the LINPACK
> >benchmark.  

> I conjecture that what they must mean is the inner-loop timing for
> the standard LINPACK code, but with zero-wait-state memory,
> i.e., something not particularly buildable.  To be fair, it is not
> unreasonable to quote such numbers, if they are clearly labeled as such,
> because a chip vendor can't control what they're put into,
> although it would be more meaningful to quotethem with a specified memory
> system of course.
> -john mashey	DISCLAIMER: <generic disclaimer, I speak for me only, etc>

Sorry this is so late a followup.  

I haven't seen the article under discussion nor information about the
DSP chips except the TMS320C30, and that information may invalidates John
Mashey's comments.   The TMS320C30 has a fairly large amount of program 
space on chip (something like 4k words) that is zero-wait state and probably
also multi-ported (but I might be getting the register file confused with
the memory buffers). 

If the inner loops fit within the on-chip memory or can be paged in and out
with the on-chip DMA logic, the TMS320C30 can do some pretty amazing things.
The other chips may also have similarly sophisticated architectures, but
I'm not sure.  (In case you can't tell, I like the TMS320x0 chips.)

Don't incriminate a vendor about flakey benchmark numbers without verifying 
that the benchmarks are in fact flakey (which I haven't actually done, but...)

Bill Smith
pur-ee!mdbs!wsmith  (A long time ago in a universe far far away, I was 
			wsmith@cs.uiuc.edu, but no longer :-)