Subject: Re: GRO: forwading ISATAP packets is very slow with kernel 4.1

From: Wolfgang Walter <[email-masked]>
Date: Wed, 15 Jul 2015 14:25:59 +0200

Am Mittwoch, 15. Juli 2015, 17:50:20 schrieb Herbert Xu:
> On Wed, Jul 15, 2015 at 02:34:41AM +0200, Wolfgang Walter wrote:
> > I wonder if the router may treat all ipv6-tcp connections of a host as a
> > single flow as all those ipv6-packets are embedded in ipv4-packets with
> > the
> > ipv4-address of the host and the ipv4-address of the isatap-gateway and
> > next- header is 41. It may only looks at those?
> 
> I think GRO is actually working fine.  Can you show me the output
> of ethtool -k eth1? If hardware TSO is enabled can you try disabling
> it to see if it helps?
> 
> Thanks,

Yes. Switching TSO off and leaving GRO on works, too.

Thanks,
-- 
Wolfgang Walter
Studentenwerk München
Anstalt des öffentlichen Rechts