[SunRescue] Loads

[Gregory Leblanc]

> -----Original Message-----
> From: koch at pz.pirmasens.de [mailto:koch at pz.pirmasens.de]
> Sent: Thursday, March 09, 2000 2:22 AM
> To: rescue at sunhelp.org
> Subject: Re: [SunRescue] Loads
> 
> 
> Hi!
> 
> >Uhm, a SS20 will easily support up to 200Mhz HyperSPARC CPUs
> >with the right OpenBoot PROMs.
> 
> Four of them??? Surely not!

Sure, you just plug them in, and add 250 extra cooling fans, and off you go.
Assuming that you can find the dual 200MHz HyperSPARC boards, that is.

> You can plug in two 200 (225???) MHz cpus, but that would not
> gain much compared to the four 95 MHz cpus. I'd even say the
> four cpus are better cause it's harder for a single person to
> occupy all cpu horsepower.

Never seen 225MHz, but I know that the 200MHz CPUs exist.  IIRC, ISI has
their root server running a 670 with quad HyperSPARC 150s?  Something along
those lines, anyway.  

> 
> >> P.S.: Sun doesn't recommend more than 2 processors in
> >> the SS20 that are faster than 50 MHz.=20
> >
> >Where'd you get this from?  And, if its true, why did Sun
> >sell the SS20 available with SM71s, SM81s, or 150Mhz HyperSPARCs?
> 
> They never sold any machine with four SM-61 or faster. The
> only four CPU configuration that sun supported ever was the
> SS20-514, e.g. two 50 MHz dual cpu modules with 1MB supercache
> each. The reason was simple: Four 60 MHZ (or faster) would
> clog the M-Bus and run slower than four 50 MHz cpus.

Possibly, that depends on use.  If you have an application that's dealing
with small datasets, you'll see a pretty big speedup going to multiple,
faster CPUS (say, quad 150MHz hypers).  For typical workstation use, you
could probably saturate the MBUS.

> 
> Notice that the Hypersparc have only 256 kb cache...

Some of them have only 256K, some have 512K.  I'm not sure, but I thought
that I'd seen some of the ones that they're manufacturing now with 1MB, but
I can't find that reference again.
	Greg