2.4. Profiling each call to a function

By default TAU profiles the total time (inclusive/exclusive) spent on a given function. Profiling each function call for an application that calls some function hundred of thousands of times, is impractical since the profile data would grow enormously. But configuring TAU with the -PROFILEPARAM option will have TAU profile select functions each time they are called. But TAU will also group some of these function calls together according to the value of the parameter they are given. For example if a function mpisend(int i) is called 2000 times 1000 times with 512 and 1000 times with 1024 then we will receive two profile for mpisend() one we it is called with 512 and one when it is called with 1024. This reduces the overhead since we are profiling mpisend() two times not 2000 times.