em interface slow down on 8.0R

[Jack Vogel]

The 82573, when onboard (LOM) is usually special, it is used by system
management
firmware.  Go to the system BIOS and turn off management, see if that
eliminates the
periodic hang.

Jack


On Sat, Dec 5, 2009 at 9:27 PM, Hiroki Sato <hrs at freebsd.org> wrote:

> John Nielsen <john at jnielsen.net> wrote
>  in <1E3C66EA-A6D3-44D7-B28E-BF068FFF16A6 at jnielsen.net>:
>
> jo> On Dec 5, 2009, at 4:40 AM, Hiroki Sato <hrs at freebsd.org> wrote:
> jo>
> jo> > Hiroki Sato <hrs at freebsd.org> wrote
> jo> >  in <20091203.182931.129751456.hrs at allbsd.org>:
> jo> >
> jo> > hr> And another thing, I noticed a box with 82573E and 82573L
> jo> > sometimes
> jo> > hr>  got stuck after upgrading to 8.0-STABLE.  It has moderate
> network
> jo> > hr> load (average 5-10Mbps) on both NICs.  It worked for a day or two
> jo> > and
> jo> > hr> then got stuck suddenly.  Rebooting the box solved the situation,
> jo> > but
> jo> > hr>  it got stuck again after a day or so.  After it happens, the
> jo> > hr>  interface does not respond.  The other functionalities of
> FreeBSD
> jo> > hr> seemed working.  Doing an up/down cycle for the NICs seemed to
> jo> > send
> jo> > hr> some packets, but it did not recover completely; rebooting was
> jo> > needed
> jo> > hr> for recovery.  This box does not have the RTT problem.  I am
> still
> jo> > hr>  not sure what is the trigger, there seems something wrong.
> jo> >
> jo> > Things turned out for this symptom so far are:
> jo> >
> jo> > - This occurs around once per 1-2 days.
> jo> >
> jo> > - Once it occurs, all of communications including ARP and IPv4 stop.
> jo> >
> jo> > - "ifconfig em0 down/up" can recover the interface. However, on doing
> jo> >   "up" after "down" the following message was displayed:
> jo> >
> jo> >   # ifconfig em0 up
> jo> >   em0: Could not setup receive structures
> jo> >
> jo> >   After trying it several times it worked.
> jo> >
> jo> >   Then, the interface seemed back to normal for a couple of minutes,
> jo> >   but it stopped again.
> jo> >
> jo> > I guess there is a kind of deadlock somewhere but not sure it is
> jo> > really related to the em(4) driver.  I will continue to investigate
> jo> > anyway.
> jo>
> jo> I'm curious, what speed/duplex is your interface using and is it
> jo> statically set or using autoselect?
>
>  No manual configuration.  Two em's are set as the following:
>
>  | media: Ethernet autoselect (1000baseT <full-duplex>)
>
>  It is mainly used for NFS server.  The actual communication speed was
>  around 700Mbps at peak.
>
> -- Hiroki
>