The CPU meter shows the problem. One core is running at 100 percent, but all the other cores are idle. Your application is CPU-bound, but you are using only a fraction of the computing power of your multicore system. What next?
The answer, in a nutshell, is parallel programming. Where you once would have written the kind of sequential code that is familiar to all programmers, you now find that this no longer meets your performance goals. To use your system’s CPU resources efficiently, you need to split your application into pieces that can run at the same time. This is easier said than done. Parallel programming has a reputation for being the domain of experts and a minefield of subtle, hard-to-reproduce software defects.
Everyone seems to have a favorite story about a parallel program that did not behave as expected because of a mysterious bug. These stories should inspire a healthy respect for the difficulty of the problems you face in writing your own parallel programs. Fortunately, help has arrived. Microsoft Visual Studio® 2010 introduces a new programming model for parallelism that significantly simplifies the job. Behind the scenes are supporting libraries with sophisticated algorithms that dynamically distribute computations on multicore architectures. Proven design patterns are another source of help. A Guide to Parallel Programming introduces you to the most important and frequently used patterns of parallel programming and gives executable code samples for them, using the Task Parallel Library (TPL) and Parallel LINQ (PLINQ).
Colin Campbellis a coauthor of Model-Based Software Testing and Analysis in C# and he has written several academic papers on mathematically rigorous approaches to software analysis. He is a founder and principal at Modeled Computation LLC, in Seattle.
Ralph Johnson is a research associate professor at the University of Illinois. He was one of the four co-authors of Design Patterns, and the leader of the group that developed the first automated refactoring tool, the Smalltalk Refactoring Browser. For the past few years, he has been working on documenting patterns of parallel programming.
Ade Miller works as a Development Lead with Microsoft’s patterns & practices group, where he manages several agile teams who deliver applied engineering guidance to Microsoft’s customers. His primary interests are in parallel computing and agile software development practices.
Stephen Toub works on the Parallel Computing Platform team at Microsoft. He spends his days designing and developing the next generation of concurrent and parallel programming models for .NET and Visual Studio.