The Tuning and Analysis Utilities (TAU) offers two methods for instrumenting C, C++, and Fortran code for profiling and tracing. The first is to instrument software by hand. While it gives the user complete control over what methods are instrumented, it has several disadvantages; the primary one being that process of inserting and removing code can be time consuming and error prone. The second method is to have TAU automatically instrument your source using the MPI wrapper library and the TAU Compiler.

If you are only interested in time spent in MPI functions, you only need to link your software to the TAU MPI wrapper library. See "Profiling MPI Software using TAU" for more information on this subject. However, most projects need a comprehensive picture of where time is spent. The TAU Compiler provides a simple way to automatically instrument an entire project. The TAU Compiler can be used on C, C++, fixed form Fortran, and free form Fortran.