info on 4D/240 crunching and compilers

[Bron Campbell Nelson]

In article <238 at noether.UUCP>, rosalia at noether.UUCP (Mark Galassi) writes:
> I came across a report that the parallelizing FORTRAN (what was it,
> power FORTRAN or super FORTRAN or whatever) was kind of flaky,
> and that the ordinary compilers only worked well without optimization
> (this is on the 4 processor machine).
> 

There was only one posting I know of that had this complaint.
He has not yet given us details of just what his problem is (are you
listening Tim?).

I (and many others) have used the compiler extensively with very little
problem.  Both the parallelizer and the optimizer work fine.  Several
hundred thousand lines of code check out.

Now, I'm an engineer, not a salesman, so I'm not going to claim that
there are absolutely no problems.  But I would claim the compiler is
as stable and reliable as the offerings of other companies.  BTW - we
use the optimizer from MIPSco.  They seem to have a reputation for good
compiler technology.

A single 25MHz cpu gets 4MFLOPS on the Linpack benchmark.  Multi-
processing speed is completely dependent on the particular code.  Some
code get nothing; some speed up tremendously.  On one of the Livermore
Kernels we get about 5.8MFLOPS single processor, and over 20MFLOPS on
4 processors.

The best thing to do is to call your nearest SGI office and try to
arrange to run your code.  The best benchmark is your application.  Don't
take my word for it; check it out for yourself!

--
Bron Campbell Nelson
bron at sgi.com  or possibly  ..!ames!sgi!bron
These statements are my own, not those of Silicon Graphics.