Hard hangs running 6-current.

[Frank Mayhar]

Doug White wrote:
> Try one of these loader tunables:
> 1. Disabling SMP (kern.smp.disabled=1)
> 2. Disabling mpsafenet (debug.mpsafenet=0)

I run with debug.mpsafenet=0 (due to a bug I ran into some time ago which I
haven't looked at recently).

The current kernel is running with HTT turned off and no SMP builtin.  So
kern.smp.disabled=1 is kind of redundant.

So no dice on either one of these.

> This may be a symptom of a deadlock we're observing on
> sparc64 in the network stack.  Either one of these should stop the
> problem, if its the issue we were seeing earlier today.

Doesn't look like it, I'm afraid.

> If you especially adventurous, try setting net.inet.tcp.do_tcpdrain=0
> instead of the options above.  This might cause mbuf exhaustion but is
> implicated in the deadlock.
> 
> This is a total hunch and I may be influenced by the time put in on this
> issue today :)

If you're interested, you might take a look at
	http://www.freebsd.org/cgi/query-pr.cgi?pr=77751
It has my results for the day.  Warning:  Lots of ath debug output.  I'm
pretty sure it's the ath driver that's the problem, particularly in light
of my most recent results.

Thanks for the ideas, though.
-- 
Frank Mayhar frank at exit.com	http://www.exit.com/
Exit Consulting                 http://www.gpsclock.com/
                                http://www.exit.com/blog/frank/