The PTScotch option for graph partitioning was recently added to the partitioning options. PTScotch uses a pseudorandom number generator for tie breaking and by default it sets the seed arbitrarily with each run. This means that the partition is usually different on repeated runs even when running on the same number of processors. This is corrected by making SCOTCH API calls to set the random seed consistently.
The PTScotch option for graph partitioning was recently added to the partitioning options. PTScotch uses a pseudorandom number generator for tie breaking and by default it sets the seed arbitrarily with each run. This means that the partition is usually different on repeated runs even when running on the same number of processors. This is corrected by making SCOTCH API calls to set the random seed consistently.