The performance of an object-oriented threads package

Presto is an object-oriented threads package for writing parallel programs on a shared-memory multiprocessor. The system adds thread objects and synchronization objects to C++ to allow programmers to create and control parallelism. Presto's object-oriented structure, along with its user-level thread implementation, simplifies customization of thread management primitives to meet application-specific needs. The performance of thread primitives is crucial for parallel programs with fine-grained structure; therefore, the principal objective of this effort was to substantially improve Presto's performance under heavy loads without sacrificing the benefits of its object-oriented interface. We discuss design and implementation issues for shared-memory multiprocessors, and the performance impact of various designs is shown through measurements on a 20-processor Sequent Symmetry multiprocessor.