Welcome! We are the Parallel Programming Laboratory.

Our goal is to develop technology that improves performance of parallel applications while also improving programmer productivity. We aim to reach a point where, with our freely distributed software base, complex irregular and dynamic applications can (a) be developed quickly and (b) perform scalably on machines with thousands of processors.

Processor virtualization is one of our core techniques: the programmer divides the computation into a large number of entities, which are mapped to the available processors by an intelligent runtime system. This separation of concerns between programmers and the system is key to attaining both our goals together.

Recovering Logical Structure from Charm++ Traces
Asynchrony and non-determinism in Charm++ programs present a significant challenge in analyzing their event traces. In this paper, published at SC’15, we present a new framework to organize event traces of parallel programs written in Charm++. Our reorganization allows one to more easily explore and analyze such traces by providing context through logical structure. We describe several heuristics to compensate for missing dependencies between events that currently cannot be easily recorded. We introduce a new task ordering that recovers logical...