Hi All, I have implemented a simulation as an OpenMesh app. In general, I have calculations on n separate meshes and occasionally a joint calculation which affects all of the meshes. I was trying to parallelize the simulation via OpenMP, assigning a separate core to each of the meshes. For testing, I am running in a regime where there are no joint calculations so all the calculations should be completely independent. Yet, none of my CPUs run at 100%, they are at around 80%. When I run it on a single core, it's constantly near 100%. I was wondering whether there are any global shared variables which prevent such parallelization or what needs to be modified in the cmake file. Currently, I do set(CMAKE_CXX_FLAGS_RELEASE "-O3 -fopenmp") and it seems to compile and use the defined number of cores. Is there anything else to be done? Note that I do not want to parallelize OpenMesh itself, I just want to parallelize my own little app, a single for loop. Thank you, Botond