| 摘要 |
PURPOSE:To reduce the required time and overhead for the equivalence guaranteeing processing, by performing the equivalence guaranteeing processing in the range represented with all journal records on each physical volume. CONSTITUTION:When an input/output request origin program 4 requests a write request to an input/output control program 5, a journal updating display processing 9 displays ''under update'' on a journal recording area on a main storage device (MM). When system-down takes place during the updata of data, the display of ''under updata'' is left in the journal record on the physical volume. Thus, after the system-down and before the use of the said logical volume, an equivalence restoration processing 12 of a system control program 6 checks the journal record on each physical volume and performs the processing of equivalence restoration as to the part of ''under update''. |
