UD is the Unreliable Datagram transport for Infiniband, specifically OpenIB. This BTL is derived from the existing openib BTL, which is RC (Reliable Connection) based.
Still a work in progress, as there is a lot of work left to do. Specifically, performance, scalability, and flow control need to be addressed.
Currently I'm playing around with different methods for handling receive buffers, as well as profiling to figure out where the time is going.
This commit was SVN r10271.
