The result is a unified concurrency model providing both thread abstractions and event abstractions. We implemented the unified concurrency model in Haskell Our implementation demonstrates how to use these techniques by building an application-level thread library with support for multiprocessing and asynchronous I/O mechanisms in Linux. The thread library is type-safe, is relatively simple to implement, and has good performance. Application-level threads are extremely lightweight (scaling to 10,000,000 threads!) and our scheduler, which is implemented as a modular and extensible event-driven system, outperforms NPTL in I/O benchmarks.
Abstract. Join patterns are an attractive declarative way to synchronize both threads and asynchronous distributed computations. We explore joins in the context of extensible pattern matching that recently appeared in languages such as F# and Scala. Our implementation supports join patterns with multiple synchronous events, and guards. Furthermore, we integrated joins into an existing actor-based concurrency framework. It enables join patterns to be used in the context of more advanced synchronization modes, such as future-type message sending and token-passing continuations.