- mvapich2: use mvapich2 selector for the alltoall operations
- impi: use intel mpi selector for the alltoall operations
- automatic (experimental): use an automatic self-benchmarking algorithm
+ - bruck: Described by Bruck et.al. in <a href="http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=642949">
- 2dmesh: organizes the nodes as a two dimensional mesh, and perform allgather
along the dimensions
- 3dmesh: adds a third dimension to the previous algorithm
