PIOMan is an I/O event manager of the PM2 software suite. It ensures communication progression using available cores and hooks in thread scheduler. It guarantees good reactivity, asynchronous communication progression, and communication/computation overlap. PIOMan is closely integrated with the NewMadeleine communication library and PadicoTM. It works with three flavors of thread scheduling: no thread, pthread, and Marcel. The pthread flavor may be composed with various runtime systems such as OpenMP. PIOMan can be used standalone to bring low level asynchronous progression in a communication library, or more simply may be used through the NewMadeleine communication library and its companion MPI implementation called Mad-MPI supporting MPI_THREAD_MULTIPLE multi-threading level.