Dear all,

I was testing your example in example/parapack/exchange with the exchange.ip modified to only test the ising case, however with more sweeps, to test the time spent.

I know that the parallel_exchange_worker gets called (visible via the line "EXMC: number of replicas on each process = 2 2", which will only be outputted by the parallel_exchange_worker). I would by this output assume that different replicas get distributed over the cores,.

The time spent in the simulation however stays the same irrespective of the number of processes I provide to MPI or not even call the MPI library at all.

I call the function in the following way:

mpirun -np 2 ./exchange --mpi < exchange.ip

resp.

./exchange < exchange.ip

Do I miss an important argument in the input file / command line argument, that prevents the parallel execution of replicas?

Best, Dominik