Writing Parallel LINQ Operators

Convention would dictate that whenever a sequential LINQ operator is written, a parallel operator should be considered to support the Parallel LINQ programming pattern users will come to expect based on the support of the other standard query operators (not a definite requirement, but should be considered). Not all operators will significantly benefit from parallelization, and without an understanding of a specific operator, it’s hard to capture explicit guidance in this area. The following types of operators make exceptionally good candidates for parallelization:

• Order-independent operators that iterate an entire source collection, for example, Where.

• Mathematical aggregate functions such as Sum.

• Operators that can yield partial results before the entire source collection has been processed by that operator (allowing the next operator to begin before all data is furnished by the previous operator).