Paraprof can now generate selective instrumentation files that may be used to re-instrument your program to reduce the instrumentation overhead. When the program is executed with the environment variable TAU_THROTTLE set to 1 TAU disables some instrumentation of routines at runtime see ???. These routines are placed in a TAU_DISABLE group. ParaProf generates a selective instrumentation file with the disabled functions as show below additionally a user may further optimize the instrumentation by specifying rules. For instance, the rules below will exclude (from instrumentation) those routines that execute over 100,000 times and take less than 10 microseconds per call.