Another reboot hang

[bob prohaska]

Hi Svata,

On Thu, May 05, 2016 at 04:38:36PM +0200, Svatopluk Kraus wrote:
> On Fri, Apr 29, 2016 at 8:52 PM, bob prohaska <fbsd at www.zefox.net> wrote:
> >
> > So far the reboot hang hasn't repeated in half a dozen or so attempts.....
> > not sure if that's good or bad.
> >
> > In the meantime the system ran stress2 (old version) for 12 hours 49 minutes,
> > the previous record was around ten hours. Interestingly, the crash did _not_
> > report "translation fault (L2)", but rather
> > "panic: pmap_growkernel: no memory to grow kernel".
> 
> 
> This panic is saying that there is no free page to alloc but the pmap
> really needs it. I have no experience with such thing, but total
> exhaustion of free page pool may happen probably. And when it happens
> in some critical place, kernel has no possibility, but panic. BTW, it
> would be nice to see output of 'show uma" and 'show malloc' from ddb.


I'll try to capture the output of "show uma" and "show malloc" the next
time the machine crashes. So far, no recurrence of the "panic: pmap_grow....."
crash, just the usual "translation fault L2...." variety or silent hang.

In the "panic: pmap_grow...." instance (April 29) it appears I mistakenly
captured the wrong top output, from an earlier crash. Can a date stamp be
added to the top output timestamp? The man page doesn't seem to say.

bob prohaska