Computer Science 335
Parallel Processing and High Performance Computing

Fall 2021, Siena College

Home     Syllabus     Schedule     Examples

Agenda

• Announcements
  • Submission/grading updates
  • Lab 7: Collective Communication should be wrapping up
  • Lab 8: More Collective Communication due next Wednesday
  • Programming Project 3: Parallelizing Jacobi Iteration due next Thursday
• Midterm exam will be October 25
  • complete in class
  • pencil and paper only
  • closed book/notes/etc
  • based heavily on labs and programming projects
  • heavy emphasis on MPI
• MPI Wrapup and Recap
  • MPI processes do not share context (memory) directly
  • An MPI implementation could use shared memory to implement message passing when processes are on the same system
  • MPI processes can be run on different computers, in which case some form of network communication is needed
  • MPI Basics: MPI_Init/MPI_Finalize, MPI_Comm_size/MPI_Comm_rank, MPI_Get_processor_name, MPI_Wtime
  • Standard point-to-point communicaton: MPI_Send/MPI_Recv, message tags, the MPI_Status structure
  • Non-blocking point-to-point communication: MPI_Isend/MPI_Irecv, MPI_Wait/MPI_Waitall/MPI_Waitany, the MPI_Request structure
  • Collective communication: MPI_Reduce/MPI_Allreduce, MPI_Barrier, MPI_Scan, MPI_Scatter/MPI_Gather
• Lab work