1. DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY Models without Borders Thomas Sterling Arnaud & Edwards Professor, Department of Computer Science Adjunct Faculty, Department of Electrical and Computer Engineering Louisiana State University Distinguished Visiting Scientist, Oak Ridge National Laborator y CSRI Fellow, Sandia National Laboratory April 5, 2011 Presentation to: PEMWS-2

2. The Status Quo DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 2

3. … or Maybe Not DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 3

4. The Challenge Enable Extreme scale computing in this decade –Exascale –Strong scale –Revolutionize STEM and national defense applications –Provide practical, programmable, dependable systems Respond to disruptive technology drivers –Multi/many core –Heterogeneous GPU –Flat-lined individual core performance Guide future system codesign –Programming models –Operating system and runtime software stack –System and core architectures DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 4

5. The Strategy Derive a new execution model –Unified to address all challenges –Single to build community wide adoption –Open to facilitate commercial products and application Develop proof-of-concept reference implementations –Developing a diversity of software realizations and tools –Targeting a diversity of present and future architectures –Spin-off early products for HPC adoption Empirical studies for quantitative evaluation –Driven by STEM and security related applications –Comprehensive for confidence in capability and reliability DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 5

6. Strategic Requirements Performance –Efficiency –Scalability Energy –Bounded power –Minimized energy Reliability –Continued operation in the presence of faults Programmability –System transparency –Portability across system classes, scales, and generations Generality –STEM –Knowledge DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 6

7. Tactical Performance Requirements Starvation –Insufficiency of concurrency of work –Impacts scalability and latency hiding –Effects programmability Latency –Time measured distance for remote access and services –Impacts efficiency Overhead –Critical time additional work to manage tasks & resources –Impacts efficiency and granularity for scalability Waiting for contention resolution –Delays due to simultaneous access requests to shared physical or logical resources DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 7

8. PEMWS-2 Objectives Inform and exchange –Share experiences and perspectives towards a common goal Build a ParalleX community –Bring together sources of complementing ideas –Identify stakeholders in government, industry, & academia –Define common needs and applications Establish a path forward –Towards a single unified execution model –Responsive to needs of industry, national agenda & missions DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 8

9. Major Topics Execution models as a service to the future Codelets Memory models Parcels for message-driven computation XPI – towards a low-level ParalleX API SWARM – many core operation Habanero – parallel programming environments Self-aware declarative control HAD-HPX results Dialog and perspectives DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 9

10. A Quick ParalleX Review Synchronous Domains AGAS – Active Global Address Space ParalleX Processes – with capabilities protection Computational Complexes – threads & fine grain dataflow Local Control Objects – synchronization and global distributed control state Distributed control operation – global mutable data structures Parcels – message-driven execution and continuation migration Percolation – heterogeneous control Micro-checkpointing – compute-validate-commit Self-aware – introspection and declarative management DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 10

11. Progress Report ParalleX execution model –Report version 1.11b HPX-3 –Targeted to conventional platforms –Missing: processes, scalable AGAS Applications –Adaptive Mesh Refinement –N-body Barnes Hut –PXGL –Linpack XPI DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 11

12. Models without Borders (1) Institutional –Not owned or claimed by any one closed organization –Not proprietary Open source –Accessible by all academic researchers –Basis for commercial deployment and deliver vehicle Target platform –Portable across classes, scales, and generations –Exploits unique strengths while not limited to them Applications –Returns parallel processing to broad range of problems –Array and graph, static and dynamic, numeric and symbolic –Data scaled and strong scaled DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 12

13. Models without Borders (2) Inter-agency –Shared responsibility and credit for development International –Recognized across continents –World-wide market for compliant products Challenge set –Robust under varied technology variations –Resilient in performance across diverse structures Convention –Not limited by status quo –Vested interests in restricting change DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 13

14. Models without Borders – Requirements Federation of Interested Organizations Charter and Mission of goals and process Stable funding Metrics of success Paradigm enabled – challenge driven VMG – velocity made good –Measured progress Reference implementation –open to all, Contributed by many –Deliverable schedule of usable components –Modular architecture for distributed development DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 14

15. Conclusions HPC has a narrow window of opportunity as it gropes for new balance point in the face of technology challenges As before a change in execution model is essential for useful progress toward capable scalable systems ParalleX is a strong contender for this new model ParalleX provides a foundation for development of a consistent and comprehensive model Intel/UDel bring needed expertise and concepts for achieving enhancements critical to ParalleX success Carpe Diem DEPARTMENT OF COMPUTER SCIENCE @ LOUISIANA STATE UNIVERSITY 15