Re: [PATCH v2] RDMA/CMA: fix iWARP adapter TCP port space usage

Steve Wise
2010-06-12T01:18:43Z

Jason Gunthorpe wrote:
> On Fri, Jun 11, 2010 at 06:40:33PM -0500, Steve Wise wrote:
>
>
>> No, everything does not work without this patch. Go read the thread
>> from 2007 (I posted the URL to it on this thread). I describe exactly
>> how an application like MPI will get incorrect behavior due to port
>> space collisions on iWARP HW.
>>
>
> I guess I missed the fact that OFED included this patch, rather than
> relying on the other administratively configured schemes you
> originally outlined. I was opining that nobody was complaining about
> the administrative stuff.. but of course nobody complains, they don't
> have to do it :(
>
> A seperate IP for iWarp always seemed to me to be the way forward on
> this. And I do mean seperate, as in TCP packets for this IP are never
> sent into the net stack seperate :|
>
>
From a user perspective, separate IP addresses for iWARP is terrible.
Further, its not even needed for IB, just iWARP. That's an unnecessary
admin pain IMO. iWARP should and can easily co-exist with the host TCP
by sharing the port space. But, as Roland stated already, maybe the
only way forward it to get end-user pressure applied at the appropriate
places! :)

Steve.