[openib-general] [RFC] [PATCH 2/7] ib_multicast 2.6.20: add ib_multicast module to track join requests from the same port

[Sean Hefty]

>I'm not sure -- who are the customers for this?  What do they want to
>do really?

The main customers I'm aware of are MPI developers.  For direct IB multicast
usage, the national labs are converting some of their MPI algorithms to use IB
multicast.  Their current approach is to create a multicast group without
specifying an MGID.  Once the group is created, the group information will be
given to other ranks out of band (using TCP or something similar), who then join
the group.

Matt can probably provide more details, but a student is doing the actual work.
I believe that they're trying to use the userspace SA patches that I posted to
the list, but how everything gets implemented under the proposed libibusa
interface probably doesn't matter much.

- Sean