On Fri, 2 Apr 2021, Larry McVoy wrote:

> SunOS 4, though I love it more than most people, is ancient history and
> is basically under one big lock for SMP.  It was a huge amount of work
> to get that code to scale in Solaris (they lifted the VM system and the
> hat layer from SunOS 4 to 5 and then went to work).

SunOS 4.1 was the best *ix I have ever used (and I've used lots over the
decades); then Slowaris came along and trashed the joint because the suits
were in charge instead of the real workers.

We never had a need for SMP, so we didn't miss it.

-- Dave