MPI scaling and running in parallel

[abukva]

I have a question about the workings of MPI version of ALPSCore. Specifically I am using ising2 tutorial and parallel version of it and I am not sure what exactly running in parallel does. For example ( number here are just for the ease of writing) if I run serial version with thermalization of 500 sweeps and total sweeps of 3000, is that the same as running parallel version with thermalization of 500 sweeps and total 1000 on 3 cores? I am not sure what do I get by running in parallel exactly, thanks for the answer.