[Beowulf] building Infiniband 4x cluster questions

[Gilad Shainer]

> They use the term "message oriented" with the description that the IB
> hardware takes care of segmentation and so forth, so that the application
> just says "send this" or "receive this" and the gory details are
> concealed.   Then he distinguishes that from a TCP/IP stack, etc., where
> the software does a lot of this, with the implication that the user has to be
> involved in that.
> 
> But it seems to me that the same processes are going on.. You have a big
> message, it needs to be broken up, etc.
> And for *most users* all that is hidden underneath the hood of, say, MPI.
> (obviously, if you are a message passing software writer, the distinction is
> important).

You can also post large message to the IB interface (up to 2GB I believe) and the IB transport will break it to the network MTU.

Gilad