[fa.info-vax] VAX 11/780 Cache parity errors

info-vax@ucbvax.ARPA (06/19/85)

From: munnari!basser.oz!boyd@seismo

I've put code into our VAX 11/780 UNIX kernel to recover from machine
checks.  Obviously that's not always possible, but I've also added
auto-reboot (ala 4BSD).

This week we recovered from a cache parity error.  The code decided
to turn off group 1 of the cache.  What I want to know is whether
the cache is flushed if I turn it off and on again?  If so,
I could turn off the failing half and then turn it back on
and it would be usable (courtesy of the flush).

I don't want to just try it.  I need to know!  In OZ no-one
knows and I don't trust VAXen. Recently I've come to
loathe the sight of them (we've had some real nasties happen at
our site, and I've had to fix them).

By the way, without group 1 our VAX ran about a factor
of 4 to 5 times slower.


Boyd Roberts

Programmer,
Dept. of Computer Science,
University of Sydney,
Australia.
--
...!decvax!mulga!basser.oz!boyd
...!seismo!munnari!basser.oz!boyd		(faster)