TWOPT_UINT("preserve_wait_ordering",preserve_wait_ordering,"only enable when getting unmatched send/recv errors in optimistic mode (turning on slows down simulation)"),
TWOPT_UINT("debug_cols",debug_cols,"completion time of collective operations (currently MPI_AllReduce)"),
TWOPT_UINT("enable_col_overhead",enable_col_overhead,"adding overhead to collective operations (currently MPI_AllReduce)"),
TWOPT_STIME("col_overhead_per_byte",col_overhead_per_byte,"collective call overhead per byte"),