Hello Forum, I received numerous comments on the sparse collectives proposal. Special thanks go to Rolf who designed an excellent example and provided many fixes to the chapter. I also decided to rename the collective from "Sparse" collectives to "Sparse Neighborhood" collectives and all functions are now called MPI_Neighbor_{alltoall,...}. The updated proposal is attached to: https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/258 It would be great to receive more reviews. Any comments are appreciated! Thanks & All the Best, Torsten -- bash$ :(){ :|:&};: --------------------- http://www.unixer.de/ ----- Torsten Hoefler | Performance Modeling and Simulation Lead Blue Waters Directorate | University of Illinois (UIUC) 1205 W Clark Street | Urbana, IL, 61801 NCSA Building | +01 (217) 244-7736