|Title:||Fine-Grain MPI for Extreme-Scale Programming|
|Conference:||Communicating Process Architectures 2014|
Department of Computer Science, University of British Columbia
Scalable computing is needed to meet the challenge of computing on ever-increasing amounts of data. Multicore and many-core adds more processing cores but still cannot keep pace with the demand for more computation. There is need for technologies to scale, not only to multiple cores within one chip but also to scale across multiple chips in one machine, and across machines in a data center.
Process Oriented programming is the design of programs as a collection of processes that communicate using message-passing. Process-oriented programs execute concurrently either by: (a) logical concurrency: sharing one processor core and taking turns executing, or (b) physical concurrency: executing in parallel on separate cores in one or more machines. Extreme scale programming is the term we use for the design of programs that use thousands and millions of such processes.
Fine-Grain MPI (FG-MPI) extends the MPICH2 runtime to support execution of multiple MPI processes inside an OS-process. FG-MPI supports fine-grain, function level, concurrent execution of MPI processes by minimizing messaging and scheduling overheads of processes co-located inside the same OS process. FG-MPI makes it possible have thousands of MPI processes executing on one machine or millions of processes across multiple machines. FG-MPI is available online from our UBC website. The purpose of the workshop will be a practical hands-on introduction to FG-MPI: how to create FG-MPI programs and run them using ``mpiexec''. I will discuss the added flexibility in executing programs and limitations. I will discuss applications and tools we have started to develop and potential extensions.
For the practical part of this workshop, it will help to have downoaded the latest FG-MPI release, together with the code examples on the download page. These are available from the "Downloads" tab on the home page. However, the work can still be followed with just pencil and paper.