I am implementing an algorithm within fortran and g77/gcc (3.3.5), on
I have tried two possibilities to perform profiling :
1) using the function second(), to have the CPU spent between two
2) using gprof : all source files have been compiled with -pg option
gprof gives some strange results. The algorithm consists in two main
steps, say step A and step B.
The usual way is to have alternatively one step A, then one step B. But
if I have 2 steps A for 1 step B, gprof do not show that double time
is spent in step A, whereas the figures based on the functions "second"
More puzzling : in a run, gprof reports that step A and step B consume
almost the same time, whereas the figures got with "second" shows that
step B is taking 90% ot the total time. These deviations are very
disturbing in the view of profiling my code !!!
Did I make something wrong using gprof ?
Thank you for your help