Re: xen and networking problems

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Fri, Oct 30, 2009 at 03:32:04PM -0600, Brook Milligan wrote:
> Manuel Bouyer writes:
>  > Did you run it with -n ? Otherwise, IP reverse resolution could cause it
>  > to stall.
> 
> Good point.  I ran it before without -n.  This time I tried it again
> with -n.  Same thing; no packets captured.  When I terminate tcpdump
> with ^C, it reports 0 packets captured/received/dropped.

very strange ...

> 
>  > tcpdump being silent makes it worse than that, as the packets are
>  > passed to bpf from the driver itself, in the interrupt routine.
> 
> So, I'm guessing this implies a problem early in the packet
> processing?  Is there a way to verify that?

Next step would be to put instrumentation in dev/ic/i82557.c,
fxp_start() and fxp_rxintr() are called (and if so, what they
do with the mbuf).

> 
>  > check that it's not running out of mbufs. vmstat -m will tell you
>  > if mbuf allocation fail (mbuf and mbuf cluster). 
> 
> See the output of vmstat -m below.  I'm not sure what to look at
> exactly.  Does this indicate any problems?

I didn't see. There's no failed allocation for mbpl and mclpl.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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