In some parallel system implementations, I/O is performed through a single processor of the system. Task parallelism in the presence of I/O assumes that all processors can perform I/O independently and this paradigm has to be supported, although it is not necessary that each processor be able to physically perform all I/O operations independently. One simple solution is to have a single designated I/O processor that performs all I/O but is not considered an executing processor and hence does not have any execution related dependences.