Basic Charm Tutorial 2008

Charm++ Tutorial Presented by: Laxmikant V. Kale Kumaresh Pattabiraman Chee Wai Lee Overview   Introduction –  Developing parallel applications –  Virtualization –  Message Driven Execution   Charm++ Features –  Chares and Chare Arrays –  Parameter Marshalling –  Examples   Tools –  LiveViz –  Parallel Debugger –  Projections   More Charm++ features –  Structured Dagger Construct –  Adaptive MPI –  Load Balancing 2   Conclusion Outline   Introduction   Charm++ features –  Chares and Chare Arrays –  Parameter Marshalling –  Examples   Tools –  LiveViz –  Parallel Debugger –  Projections   More Charm++ Features –  Structured Dagger Construct –  Adaptive MPI –  Load Balancing 3   Conclusion Developing a Parallel Application Seek optimal division of labor between “system” and programmer Decomposition done by programmer, everything else automated Decomposition Mapping Charm++ Scheduling Specialization 4 Automation Virtualization: Object-based Decomposition  Divide the computation into a large number of pieces – Independent of number of processors – Typically larger than number of processors  Let the system map objects to processors 5 Object-based Parallelization User is only concerned with interaction between objects System implementation User View 6 Message-Driven Execution  Objects communicate asynchronously through remote method invocation  Encourages non-deterministic execution  Benefits ...