Before Choosing and Marking the Best Parallel Opportunities

Before you can mark the best parallel opportunities by adding annotations , you need to choose likely places to add parallelism. This section introduces several topics that explain factors you should consider as you closely examine the candidate code regions and their execution.

Each code region where you might add parallelism consists of a single parallel site and one or more parallel tasks enclosed within the parallel site. Each parallel site defines the scope of parallel execution. You can have multiple parallel sites in a program.

No matter how much you improve one part of your program, the program cannot complete any faster than the part that you did not speed up. So, focus your efforts on the parts of your program that use the most time.

Use the Survey Report provided by the Survey tool to help you understand where your program spends it time.

For more complete information about compiler optimizations, see our Optimization Notice.