on 10/26/01 7:03 PM, Chuck Silvers at chuq@chuq.com wrote:

> the bug in the new pmap that people have complained about causes a panic
> when some sanity-checking code notices that the internal pmap state
> has become inconsistent.
> 
> if you haven't had any problems with the old pmap, don't switch to the new
> one.
> these pmap bugs are the sort that seem to only affect some people and not
> others.  I've never had any problems with either pmap myself, but then
> I don't do much with my powermac.

With a -current kernel and the old pmap, the machine I'm working with
reliably panics in short order (less than 1/2 hour).  I never saw this panic
in testing, but when I deployed the new machine it made for an exciting day
until I reverted to the old server.

When you're talking about IS, exciting == bad.

This machine _does_ get used for a lot, and random panics just aren't
acceptable.

Is someone actively working on fixing the bugs in the new pmap?  I really
hate to hear that -current macppc kernels Just Aren't Reliable with either
pmap, but that seems to be what the evidence suggests.

A 1.5.2 kernel just doesn't make good use of the 1.25G of RAM in this box,
but that's what I'm planning to deploy this weekend, if I can figure out the
proper settings for BUFPAGES & friends.  I may end up downgrading to 512M to
get the kernel to boot...

-- monroe
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Monroe Williams                                  monroe@criticalpath.com