🚀 go-pugleaf

In article <706@brl-sem.ARPA> ron@brl-sem.ARPA (Ron Natalie <ron>) writes:
>Last time I checked (and I checked Pyrmaid recently) Arete, Pyramid, and
>Elxsi were not 12 MIPs.

I had understood the poster to say that *two* processors gave 12 MIPS, which
would make it about the same as Pyramid's 9820 dual CPU system. It has been
since pointed out to me that it was 12 MIPS per CPU, which is a very different
story; $400K would buy you 24MIPS or so. Elxsi claims 10MIPS per CPU, Pyramid
7, and Arete 2.5, and so on.

>The bus on the new Gould is much faster than every CPU you listed.

Elxsi's bus is claimed to be 330Mbytes/second, more than double the Gould NPL.
(Pyramid's is 40MB.) Elxsi uses that huge bandwidth primarilly for multiple
processors, and indeed it is the Pyramid's bus bandwidth that limits the
number of CPUs you can throw on it. (Caching helps a lot, but the CPUs do need
to reference main store once in a while. :-)) 

I'd be curious to hear people's thoughts on whether all that bandwidth is
really usable by I/O. The best disks/controllers you can buy today only putter
along at, what, 20Mbytes/sec? And the Unix file system is two slow and grody
to really take advantage of more than about an eighth of that with a 12 MIPS
CPU behind it. Yes, there's raw disk I/O, but how much is that used outside of
dedicated database applications? 

(Honest questions, I really don't know. I'm just a comm hacker. :-))

<csg>