Overlapping input/output

A reduction in processing time can be achieved by means of asynchronous I/O operations. Once an I/O operation has been initiated, control is immediately returned to the program in order to enable other processing to take place in parallel with the physical I/O. The next I/O operation is then initiated using a second I/O area that does not overlap the first, and so on.

The figure 24 illustrates the overlapping of processing and input operations.

Figure 24: EAM: overlapping input/output