The tprof command is recommended for multiple-process profiling. However, both processes write a gmon.out file in the directory from which you run the parent process, overwriting one of them. Profiling is an attribute of the environment of each process, so if you are profiling a process that forks a new process, the child is also profiled. Profiling using the gprof command is problematic if your program runs the fork or exec subroutine on multiple, concurrent processes. Profiling with the fork and exec Subroutines Cycles are also shown, with an entry for the cycle as a whole and a listing of the members of the cycle and their contributions to the time and call counts of the cycle.A similar display above the function shows how the time of the function and the time of its descendents are propagated to its (direct) call-graph parents. Below each function entry are its (direct) call-graph children, with an indication of how their times are propagated to this function. A second listing shows the functions sorted according to the time they represent, including the time of their call-graph descendents.Cycles are discovered, and calls into a cycle are made to share the time of the cycle. The times are then propagated along the edges of the call graph. This listing gives total execution times and call counts for each of the functions in the program, sorted by decreasing time. First, a flat profile is produced similar to that provided by the prof command.Note: Symbols from C++ object files have their names demangled before they are used. Programs not recompiled with the -pg option do not have the mcount subroutine inserted, and therefore keep no record of who called them. During program execution, each time a parent calls a child function the child calls the mcount subroutine to increment a distinct counter for that parent-child pair. The -pg option causes the compiler to insert a call to the mcount subroutine into the object code generated for each recompiled function of your program. If more than one profile file is specified, the gprof command output shows the sum of the profile information in the given profile files. The -pg option also links in versions of library routines compiled for profiling, and reads the symbol table in the named object file ( a.out by default), correlating it with the call graph profile file. The profile data is taken from the call graph profile file ( gmon.out by default) created by programs compiled with the cc command using the -pg option. To find out which functions (routines) in the program are using the CPU, you can profile the program with the gprof command. The gprof command is useful in identifying how a program consumes CPU resource. The effect of called routines is incorporated into the profile of each caller. The gprof command produces an execution profile of C, Pascal, FORTRAN, or COBOL programs. AIX Version 4.3 Commands Reference, Volume 2

C gprof