1. An apparatus useful in the recovery from faults within a computing system, the apparatus comprising: counting means for counting executed machine instruction; and checkpoint recording means, including means for recording a value of the counting means, for recording wherein the checkpoint comprises an initial checkpoint and information transfers occurring during a checkpoint interval, the initial checkpoint comprising data in central processor unit registers and data in cache memory at the beginning of the checkpoint interval, and the information transfers comprising, during the checkpoint interval, data transferred directly to the central processor unit from an I/O controller, data transferred to the central processor unit from the cache memory, and data from an interrupt to the central processign unit.