Section: Partnerships and Cooperations

International Initiatives

Inria Associate Teams Not Involved in an Inria International Labs

IOComplexity

• Title: Automatic characterization of data movement complexity

• International Partner (Institution - Laboratory - Researcher):

  • Ohio State University (United States) - P. Sadayappan

  • Colorado State University (United States) - Louis-Noël Pouchet

• Start year: 2015

• See also: https://team.inria.fr/corse/iocomplexity/

• The goal of this project is to develop new techniques and tools for the automatic characterization of the data movement complexity of an application. The expected contributions are both theoretical and practical, with the ambition of providing a fully automated approach to I/O complexity characterization, in stark contrast with all known previous work that are strictly limited to pen-and-paper analysis.

  I/O complexity becomes a critical factor due in large part to the increasing dominance of data movement over computation in energy consumption for current and emerging architectures. This project aims at enabling: 1. the selection of algorithms according to this new criteria (as opposed to the criteria on arithmetic complexity that has been used up to now); 2. the design of specific architectures in terms of cache size, memory bandwidth, GFlops etc. based on application-specific bounds on memory traffic; 3. higher quality feedback to the user, the compiler, or the run-time system about data traffic, a major performance and energy factor.

PROSPIEL

• Title: Profiling and specialization for locality

• International Partner (Institution - Laboratory - Researcher):

  • Universidade Federal de Minas Gerais (Brazil) - Computer Science Department - Fernando Magno Quintão Pereira

• Start year: 2015

• See also: https://team.inria.fr/alf/prospiel/

• The PROSPIEL project aims at optimizing parallel applications for high performance on new throughput-oriented architectures: GPUs and many-core processors. Traditionally, code optimization is driven by a program analysis performed either statically at compile-time, or dynamically at run-time. Static program analysis is fully reliable but often over-conservative. Dynamic analysis provides more accurate data, but faces strong execution time constraints and does not provide any guarantee. By combining profiling-guided specialization of parallel programs with run-time checks for correctness, PROSPIEL seeks to capture the advantages of both static analysis and dynamic analysis. The project relies on the polytope model, a mathematical representation for parallel loops, as a theoretical foundation. It focuses on analyzing and optimizing performance aspects that become increasingly critical on modern parallel computer architectures: locality and regularity.

Participation in Other International Programs

• EnergySFE (STIC-Amsud)

  • Leader: University Federal of Santa Catarina (UFSC): Màrcio Castro

  • Partners: UFSC (Florianapolis, Brazil), UFRGS (Porto Alegre, Brazil), ESPE (Ecuador), CNRS (LIG/Corse , TIMA, LSPSC)

  • http://energysfe.ufsc.br/

  • Duration: January 2016 - December 2017

  • Corse participants: Jean-François Méhaut, François Broquedis, Frédéric Desprez

  • The main goal of the EnergySFE research project is to propose fast and scalable energy-aware scheduling and fault tolerance techniques and algorithms for large-scale highly parallel architectures. To achieve this goal, it will be crucial to answer the following research questions:

    • How to schedule tasks and threads that compete for resources with different constraints while considering the complex hierarchical organization of future Exascale supercomputers?

    • How to tolerate faults without incurring in too much overhead in future Exascale supercomputers?

    • How scheduling and fault tolerance approaches can be adapted to be energy-aware?

    The first EnergySFE workshop was organized by the Corse team at the Inria Minatec building in September 2016.