[rescue] sparc 2 and 10 things

[Doug McIntyre]

On Thu, Dec 15, 2016 at 08:39:59AM -0500, john wrote:
> Back to the SS 10 CPU question.  Given that multi processors may not do 
> much more than a single would running 4.1.4, there is still the issue of 
> pep. We replaced sun processors with Ross on the SS2's in 1991 IIRC. I 
> may be completely confused here but it seemed like one conversion 
> doubled performance.

I suppose everything is relative.

As others have said, multi-CPU's do work fine in SunOS 4.1.4, it just
didn't have the fine grained kernel locking that Solaris had.
"Theoretically" Solaris would have better multi-CPU performance over
4.1.4, but of course, that wouldn't really have mattered until Solaris
was usable and fast enough to actually run, somewhere around 2.5 or 2.5.1
which by that time UltraSPARC was out with no 4.1.4 support, so its not
like you chould choose any longer if you were getting new hardware. 

The performance of multi-CPU SS10 was much better than single CPU of
around the same clock speed and worked just fine. SunOS 4.1.4 can run
multiple CPUs. You are probably still a bit brain washed still from Sun
marketing that Solaris is the only "proper" multi-CPU OS, but SunOS
worked quite well too. 

Clock speed does tend to win all arguments. A HyperSPARC 150 was
much faster than dual SM51s, especially if you had the dual.