1. X10: Performance and Productivity at Scale
Programming Models -- The Road Ahead
11/16/10
X10: Performance and Productivity at Scale
Vijay Saraswat and Dave Grove
IBM TJ Watson
Nov 17, 2010
Asynchronous PGAS

2. Programming Models -- The Road Ahead
11/16/10
What is X10?
Asynchronous PGAS Programming Model in a Java-like language
Not Java!
No threads or locks
Explicitly designed for concurrency and parallelism
Parallelism: places, at
Concurrency: async, finish, atomic, when, clocks
Sequential: closures, structs, constraint-based types, true generic types, local type inference
Target architectures
x86, cluster of x86/Power, big Power SMPs, 100K core Power boxes, BlueGene, GPGPUs …
Two compilation paths
Compile to JVM
Run on a cluster of VMs
Compile to C++
Runs on BG, clusters,…
Both paths use a high performance run-time.
No actors, MPI, OpenMP, CUDA…
Asynchronous PGAS

3. Principles and Practice of Parallel Programming
Programming Models -- The Road Ahead
11/16/10
Principles and Practice of Parallel Programming
Course objective
Teaching fundamentals of data-structure design, analysis, implementation for efficient parallel execution
Programming abstractions for concurrency
Techniques for reasoning about behavior and performance of parallel programs
Course history:
Fall 09 (23 students)
Fall 10 (16 students)
Assignments, programming project in X10 (cluster of x86)
Course structure
Unit I: Introduction
Unit 2: Introduction to X10
Unit 3: Abstract performance model (task graphs)
Unit 4: Concrete performance model
Unit 5: Safe parallelization
Unit 6: Indeterminacy
Unit 7: Blocking synchronization
Semester long programming project
Metric: speedup
async, finish, clocks, at, commutativity
atomic
when
Asynchronous PGAS