[comp.sys.sun] Large number of processes on 470/490

mark@cbfsa.att.com (Mark R Horton) (11/29/90)

Apologies in advance if this has already been covered in this group;
please email responses and I'll summarize if there is interest.

The Sun 4 has historically done poorly when there are many processes
trying to run, because it has only 16 hardware contexts and the overhead
to change processes is very high if the new process isn't one of the core
16.  Thus, if the load average rises above about 18 the machine starts to
have trouble.

Sun says that the 470 and 490 solve this problem by increasing the number
of contexts to 64 and drastically reducing the overhead to change
processes.

Has anyone done any experimentation on a 470 or 490 that can confirm or
deny that the problem is fixed?  At what point does such a machine start
to have similar trouble?

Thanks,
	Mark.Horton@ATT.COM