Is LRO on by default? If not how can we enable it? --- Regards Barry Mavin Recital Corporation
> From: Boris Shpolyansky <bo...@mellanox.com> > Date: Thu, 10 Sep 2009 19:31:35 -0700 > To: Shirley Ma <mashi...@us.ibm.com> > Cc: Roland Dreier <rdre...@cisco.com>, <general@lists.openfabrics.org> > Subject: RE: [ofa-general] mlx4 second port lro issue > > Shirley, > > Are you referring to actual Ethernet frame size or to TCP message size? > If the port MTU set to 1500 it will reject Ethernet frames larger than > this size, this has nothing to do with the LRO. > LRO is a TCP offload that improves CPU utilization on the TCP receiver > by combining multiple packets belonging to the same TCP stream to a > single buffer and transferring it to the TCP stack as a single large > packet. > > Boris Shpolyansky > Sr. Member of Technical Staff, Applications > > Mellanox Technologies Inc. > 350 Oakmead Parkway, Suite 100 > Sunnyvale, CA 94085 > Tel.: (408) 916 0014 > Fax: (408) 585 0314 > Cell: (408) 834 9365 > www.mellanox.com > > -----Original Message----- > From: Shirley Ma [mailto:mashi...@us.ibm.com] > Sent: Thursday, September 10, 2009 7:08 PM > To: Boris Shpolyansky > Cc: Roland Dreier; general@lists.openfabrics.org > Subject: RE: [ofa-general] mlx4 second port lro issue > > Hello Boris, > > On Thu, 2009-09-10 at 14:16 -0700, Boris Shpolyansky wrote: >> Dumb question: what was the MTU setting of the eth interface >> associated >> with port 2? Dropping jumbo frames has nothing to do with LRO - it is >> plain layer 2 functionality. > > ifconfig shows both port1 and port2 mtu are 1500. port 2 does't drop > jumbo frames. The problem is the LRO is on for both interfaces so the > interface will get large packet (packet size 1848). port1 can receive it > and process it, but not port2. If I disables lro by reloading module > with num_lro=0, then it will get small packet, and port2 works fine. > > My question here is why port1 can work well for lro but not port2. > > Thanks > Shirley > > _______________________________________________ > general mailing list > general@lists.openfabrics.org > http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general > > To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general _______________________________________________ general mailing list general@lists.openfabrics.org http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
