em interface slow down on 8.0R

Joshua Boyd boydjd at jbip.net
Tue Jan 26 05:03:07 UTC 2010

I've been having a similar problem with my network dropping completely on my
8-STABLE gateway/firewall/fileserver. My setup is a little different, as I
have re0 and ral0 bridged for LAN, and em0 for WAN. I've just turned off TX
checksum offloading to see if that makes any difference.

On Mon, Jan 25, 2010 at 1:49 PM, Lars Eggert <lars.eggert at nokia.com> wrote:

> Hi,
> On 2010-1-25, at 19:38, Nick Rogers wrote:
> >> On Mon, Jan 25, 2010 at 10:22 AM, Pyun YongHyeon <pyunyh at gmail.com>
> wrote:
> >> I'm not sure you're seeing a checksum offload bug of em(4) but the
> >> bug is easily reproducible in VLAN environments. If the issue is
> >> gone when you disable TX checksum offloading, see kern/141843 for
> >> for more detailed information as well as fix.
> >>
> > Good to know, but I am having a similar problem on another em(4)
> interface that has no VLAN interfaces.
> FYI, I also have these issues without using VLANs, and turning off TSO
> fixed them.
> Lars

Joshua Boyd

E-mail: boydjd at jbip.net


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