Intel® C++ Compiler 19.0 Developer Guide and Reference

Timing Programs and Program Segments

Intel® Cilk™ Plus is a deprecated feature. Use OpenMP* or Intel® Threading Building Blocks instead. For more information see Migrate Your Application to use OpenMP* or Intel® TBB Instead of Intel® Cilk™ Plus.

You should measure performance to find and understand bottlenecks. Even small changes in a program can lead to large and sometimes surprising performance differences. The only reliable way to tune performance is to measure frequently—preferably on a mix of different systems. Use any tool or technique at your disposal, but only true measurements will determine if your optimizations are effective.

Performance measurements can be misleading, however, so it is important to take a few precautions and be aware of potential performance anomalies. Most of these precautions are straightforward but may be overlooked in practice.