RS <[EMAIL PROTECTED]> writes: > In the abbreviated version of the code, the output of "time ./program" is > > real 0m57.768s > user 0m40.878s > sys 0m7.812s
This says: most of the time is spent in user-level code. Such code consists of: 1. your own code (main exe, libraries, etc.), and 2. "system" libraries (libc.dylib (or whatever it's called on OSX)) > For the same abbreviated code, gprof claims that both the total time > and self time of all the functions (including main) are 0.0. Gprof can only measure code that was compiled with '-pg' (1 above), but not code compiled without it (2 above). > guess I don't understand the fundamental thing about gprof, because I > thought I could get some idea of how much time is spent in each > function It can. The problem is that (apparently) 99.99% of time is spent *not* in your functions, but in "system" code. In order for gprof to tell you which *your* functions contribute to the execution time (by calling some "slow" system functions), you must link with '-pg'-compiled versions of system libraries (as I've already told you). > The (static) library, libfoo.a, that I link with, is my own defined > library, which I have put all the functions in. It is not a system > library. And it (apparently) doesn't contribute much to total execution time. Note that even if you don't see "system" libraries on your link line, that doesn't mean none are used: compiler adds such libraries automatically. > Are you saying that gprof can not go into the libraries? No. I am saying that gprof can not go into non-'-pg'-compiled libraries, and (on some platforms) not into dynamic libraries. Cheers, -- In order to understand recursion you must first understand recursion. Remove /-nsp/ for email. _______________________________________________ help-gplusplus mailing list help-gplusplus@gnu.org http://lists.gnu.org/mailman/listinfo/help-gplusplus
