The design of a task parallel library

The Task Parallel Library (TPL) is a library for .NET that makes it easy to take advantage of potential parallelism in a program. The library relies heavily on generics and delegate expressions to provide custom control structures expressing structured parallelism such as map-reduce in user programs. The library implementation is built around the notion of a task as a finite CPU-bound computation. To capture the ubiquitous apply-to-all pattern the library also introduces the novel concept of a replicable task. Tasks and replicable tasks are assigned to threads using work stealing techniques, but unlike traditional implementations based on the THE protocol, the library uses a novel data structure called a ‘duplicating queue’. A surprising feature of duplicating queues is that they have sequentially inconsistent behavior on architectures with weak memory models, but capture this non-determinism in a benign way by sometimes duplicating elements. TPL ships as part of the Microsoft Pa...

• Type: Conference
• Year: 2009
• Where: OOPSLA
• Authors: Daan Leijen, Wolfram Schulte, Sebastian Burckhardt
• Keywords: Library, OOPSLA 2009, Replicable Tasks, Security Privacy, Task Parallel Library