On Thu, 2005-12-22 at 14:34, Sean Hefty wrote: > >I'm soliciting feedback from the MPI and other application developers > >regarding > >which OpenIB APIs they will be targeting with their implementations. > >Specifically, myself and some of the other IB developers are interesting in > >knowing if userspace applications will be written to the RDMA CMA interface, > >the > >IB CM API, or some other abstraction. > > To help clarify the trade-offs: > > The CMA allows the use of IP addressing for connection establishment and > abstracts device hotplug. It also operates over any type of RDMA device. > > A disadvantage of using the CMA is that it may not select the best set of > paths > between two or more nodes.
What defines best ? Is this preference or disjointedness or something else ? Note path selection may be important in subnets when LMC > 0. > The IB CM also permits path failover on a single > HCA. Use of the IB CM requires that clients also interface with the IB SA to > obtain path records. Note that interaction with the SA will be required for MPI when multicast groups are to be used. > My personal recommendation would be for applications to use the CMA, but that > does result in losing some flexibility. Would the CMA ultimately support path failover ? -- Hal _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
