Call tree/profiler

User Support
1

Hi,

I am trying to create a call tree for openmc, I am trying to use a profiler to do it so I have 2 questions, does someone already have a call tree for both the c++ and python sides and is anyone using a profiler, gprof, prof or forge? I keep telling cmake to build using gprof but it keeps ignoring my directives. I’m not a cmake expert so i’m obviously doing it wrong.

Thanks,

Mike

2

Hi Mike,

In our CMakeLists.txt file, there is a “profile” option that adds flags necessary for doing profiling (if using gcc). When you’re running cmake, add -Dprofile=on to make sure you get these flags. I believe gprof doesn’t work well for us currently because most of OpenMC is built as a shared library. If you changed it to build libopenmc as a static library, you might be able to get gprof to work. Generally I use the Linux perf profiler for OpenMC, so the workflow looks something like:

cmake -Dprofile=on …
make
cd <directory_with_inputs>
perf record -g openmc
perf report

I know myself and others have also used Intel VTune with success, if that’s an option for you.

Best regards,
Paul

3

Hi,

Thank you Paul, perf is working out well, for the c++ code. perf script > scr.out then gprof2dot gives a nice (huge) call tree.
For python I settled on cProfile (python -m cProfile -o output.pstats run_depletion.py) and then gprof2dot gives a somewhat smaller tree (but still huge.)

Thanks again,

Mike