[rescue] What to do with the SS20

Steven M Jones smj+rescue at crash.com
Sun Jun 22 21:30:23 CDT 2014

On 06/22/2014 05:37 PM, Sandwich Maker wrote:
> " Also, I believe all SunOS 4 releases can only have one CPU executing
> " kernel code at a time. I'm not sure if technically you have to call that
> " asymmetric multiprocessing, rather than SMP.
> now that you mention this, i think you're right.  it wasn't a problem
> for ${WORK[1995]}, as we were doing complex fpga layouts and sims, and
> 2 cpus meant the engineers - and the systems - could do useful work on
> one cpu while the big heavy sim app hogged the other one.

I was at a place for most of 1991 where I first met Solbourne gear, and
one major use was to run Synopsys and other EDA software. Whatever the
task, the Solbournes just soaked up the load and kept going.

> ... solbourne dug into the kernel
> code and implemented fine-grained spinlocks, but sun basically just
> put one giant spinlock around the entire kernel.  since solbourne
> licensed sun's codebase, why couldn't sun just build on their work?

I suspect the answer lies with the work Sun was already doing on SVR4
with AT&T in the late 80s, so that they already had a path that would
lead there with the new OS. Why do more than temporarily hold off the
threat from Solbourne and others until that was ready?  But I wouldn't
mind finding out from those in the know. Especially if it's something
like, "Oh, we didn't think they'd do that, so we didn't include it in
the license terms..."


More information about the rescue mailing list