[ofa-general] OFED-1.3beta IPoIB testing questions

[Or Gerlitz]

Shirley Ma wrote:
> I just touch tested ofed-1.3 beta IPoIB. And found there was a kernel 
> parameter hw_csum being added in IPoIB. I have several questions here:
> 1. Why not using ethtool to set up these HW_CSUM flags?
> 2. I haven't looked at the detailed code yet, is that possible with this 
> flag, TCP/IP will not do CSUM for HCA which has no TCP/IP offload support? 
> If so, then these packets should be limited to be IB network. Routing to 
> ethernet network, the packets would be dropped. If not, I tested IPoIB-UD, 
> why I saw 30% improvement with hw_csum set in none connectX mthca SDR 
> environment?
> 3. I saw switching between IPoIB-cm and IPoIB-ud corrupted interface IP 
> address (unicast address, subnet mask, broadcast address. Anybody saw the 
> same problem?

Shirley,

Please take a look on slide 13 in Dror's presentation @
http://openfabrics.org/archives/nov2007sc/IPoIB-UD%20SO.pdf

Over the session some criticism has been expressed by developers at the 
audience that the patch which was merged to OFED 1.3 did not address the 
comments made over the list, Dror apologized and said this will be taken 
care of.

Also please note that Roland is the upstream kernel IB stack maintainer 
where the process to have this or that code piece in OFED does not 
include posting the patches to review nor getting feedback from him as a 
must for inclusion.

Or.