> Quoting Moni Levy <[EMAIL PROTECTED]>: > Subject: Re: [ofa-general] [Bug 450] New: IPoIB BW drop (measured with iperf) > with mtu=1500 on x86 RH4UP3 > > On 3/13/07, Michael S. Tsirkin <[EMAIL PROTECTED]> wrote: > >> >Why are you playing with ifc mtu? > >> > >> We needed to do some IP forwarding tests between IB and Ethernet and > >> wanted to have the same MTU for the eth0 and ib0 interfaces, after > >> that we reproduced that in a peer to peer configuration. > > > >OK but PMTU discovery would do this better, won't it? > > I'm not sure (it will probably drop some packets at the beginning).
Can you check pls? > Anyway lower MTU should work. Manually tweaking MTU seems to be broken in lots of systems - I sometimes see the same behaviour with gigabit ethernet. > >As a side note, with 1.5K MTU it's probably better to use datagram mode > >anyway. > > Now I see that I missed that in the report. We used datagram mode. Did you try checking ethernet BW on the same machine? -- MST _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
