Next Generation MPI Programming: Advanced MPI-2 and New Features in MPI-3

Presenters

  Torsten Hoefler, University of Illinois at Urbana-Champaign and ETH Zürich
  Martin Schulz, Lawrence Livermore National Laboratory

Host

Abstract

The Message Passing Interface is the de-facto standard for parallel programming. It offers a comprehensive set of point-to-point and collective communication operations and One Sided access semantics. MPI's complexity is manifold: novice users can compose parallel programs with only six MPI function calls, while advanced users can benefit from the higher abstraction and performance portability of the 200+ remaining calls. Often overlooked features, such as datatypes, can directly optimize program execution and reduce energy consumption. This tutorial will educate MPI users about advanced features in the current MPI-2.2 and is the first to present a detailed overview of new features and capabilities as well as changes in the upcoming MPI-3.0. We will discuss advanced use of MPI datatypes, nonblocking point-to-point and nonblocking collective communications, topology mapping, and neighborhood collective communication. We will also discuss advanced usage of MPI-2 and MPI-3 One Sided operations, which represent a PGAS model to the user. Hybrid programming principles, language bindings and an overview of tools and new query interfaces will round up our presentation of advanced MPI-3.0. We expect that tutorial attendees will be able to use MPIs advanced features to improve their existing code and their productivity for writing new applications.

Detailed Description

This tutorial will introduce advanced MPI-2.2 and new MPI-3.0 functions and concepts. We will demonstrate use-cases and examples for the discussed concepts. New concepts such as nonblocking or neighborhood collective communication are intended to raise the level of abstraction to allow the user to specify ``what is done'' and not ``how it is done'' of his algorithms to the library which can then optimize to the particular target architecture. Existing concepts, such as MPI datatypes can often be used to improve application performance and programmer productivity.

The attendees will understand how the concepts are intended to function and under which circumstances the functions should be used or when they should not be used. We will also discuss MPI algorithms for advanced communication problems.

The new MPI-3.0 standard will introduce new interfaces to query and manipulate both configuration and performance data through the newly defined MPI tool information interface. We will provide a first look at its capabilities and provide a series of use cases for usage both inside of applications as well as tools.

Additionally, MPI-3 includes s series of small updates, changes and additions, which we will summarize for the attendees along with a description of their impact and consequences for application developers. We intend for this section to raise awareness for minor features often overshadowed by the major updates, but still provide powerful additions for the optimization or efficient design of MPI codes. We will further briefly discuss open proposals for future MPI versions as well as the process that's behind the standardization of MPI.

Industry (ISVs), academics, researchers, developers

50% Intermediate + 50% Advanced

We assume that people are familiar with MPI basics and that they have used MPI before. However, several new features target the intermediate level while others will be more advanced.

Familiarity with C (or Fortran). Some familiarity with MPI (used it before and understand basic concepts). Basic concepts of distributed memory parallel programming.

Preliminary Agenda