JP2664197B

PURPOSE:To curtail an exclusive overhead to an updating request by constituting the respective journals which are connected to a journal setting processing part and an updating end processing part, of an entry having information of 'the blocks which are being updated are continuous something blocks from a relative something block diagram in a duplex volume'. CONSTITUTION:An entry of journals 14X, 14Y is made usable cyclically in advance, and a size of the journals 14X, 14Y is allowed to correspond to a load of a duplex volume and determined suitably. That is, the size of the journal is determined by the number of entries, and such a problem as the size of the journal is different at every kind of a device is obviated. Therefore, the equivalent property guarantee processing system for the duplex volume is constituted of a processor 10 containing an I/O issue processing part 11 for an updating request containing a journal setting processing part 12, and an updating end processing part 13 for an I/O end interruption, a physical volume 15X and 15Y are connected to the processing part 12, and the journal 14X and 14Y are connected in advance to the processing part 12 and 13.