ESIX and Caching Motherboards

[Paul De Bra]

In article <1991Mar29.031716.25197 at druid.uucp> darcy at druid.uucp (D'Arcy J.M. Cain) writes:
>Not only is it true but it is true for one of Everex's own motherboards!
>I bought an Everex Step 386/25 for two reasons:
>...
>It has been real annoying to have to run the system with the cache
>turned off.  Especially annoying is when I upgraded from 4 Meg to 8.

I have succesfully installed (not just run) AT&T sVr3.2.1, ISC 2.0.1 and
Esix rev D on the Step 386/25 with the (128k) cache ENABLED.

The only possible problem I've encountered was that when reading a large
number of small files form a cpio tape with the high speed everex 1/4inch
driver some files were corrupt while cpio did not give an error.
With the 'standard' driver (Esix or AT&T) this never happened.

I believe most 386 machines follow the convention that addresses with the
most significant bit on are equivalent to the same addresses with that bit
turned off except for bypassing the cache. Software that follows that
convention has no problem.

So turn on that cache! I have encountered so many systems with problems
(and read or heard about many more) that I'm convinced the few extra bucks
to get the Everex Step 386/25 was a worthwile investment.

Paul.
(debra at win.tue.nl, debra at research.att.com)