Invalid data detection, recording and nullification

摘要: Often in DASD subsystems, circumstances can occur which prevent the full transfer of required data from channel to subsystem during a write operation. The disclosed methods prevents this later being read and treated as valid by host processor. This is achieved marking invalid within storage once it determined that error has occured. Subsequently, upon reading data, processor be made aware invalidity treat accordingly. In second embodiment, discarded rather than stored over previous version before ever on DASD.