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<p><tt>Tziporet Koren <tziporet@dev.mellanox.co.il> wrote on 12/02/2007 05:30:42 AM:<br>
<br>
> Shirley Ma wrote:<br>
> > I just touch tested ofed-1.3 beta IPoIB. And found there was a kernel <br>
> > parameter hw_csum being added in IPoIB. I have several questions here:<br>
> > 1. Why not using ethtool to set up these HW_CSUM flags?<br>
> > <br>
> This is experimental code - Dror explained it in OFED devcon (Or sent <br>
> you the pointer)<br>
</tt><br>
<tt>So this code won't be in mainline kernel.</tt><br>
<br>
<tt>> > 2. I haven't looked at the detailed code yet, is that possible with this <br>
> > flag, TCP/IP will not do CSUM for HCA which has no TCP/IP offload support? <br>
> > If so, then these packets should be limited to be IB network. Routing to <br>
> > ethernet network, the packets would be dropped. If not, I tested IPoIB-UD, <br>
> > why I saw 30% improvement with hw_csum set in none connectX mthca SDR <br>
> > environment?<br>
> Arbel HCA also support checksum offload - so you will see improvement in <br>
> this HCA too.<br>
> > 3. I saw switching between IPoIB-cm and IPoIB-ud corrupted interface IP <br>
> > address (unicast address, subnet mask, broadcast address. Anybody saw the <br>
> > same problem?<br>
> > <br>
> Can you give more details? We change here between CM and UD mode all the <br>
> time.<br>
> What is the exact scenario you run?<br>
> <br>
> Tziporet<br>
> <br>
</tt><br>
<tt>Yes, I will rerun my test to find the sequence to reproduce this.</tt><br>
<br>
<tt>thanks</tt><br>
<tt>Shirley</tt></body></html>