Patent ID: 8234446
Filing Date: 2012-07-31
Classification: G06F

Abstract:
1. A disk array apparatus in which each storage area in multiple storage devices is divided into multiple unit storage areas, multiple pieces of data and parity data generated based on the multiple pieces of data are grouped into a parity group, and the multiple pieces of data and the parity data in a same parity group are distributed and stored in the multiple unit storage areas in the multiple storage devices, the disk array apparatus comprising: a parity-data generating unit that generates, in response to a write request containing update data, updated parity data in a parity group to which the update data belongs; a time-series-information generating unit that generates time-series information indicating an anteroposterior relationship during writing between the update data and existing data stored in an unit storage area to which the update data is to be written; a time-series-information adding unit that adds the time-series information, generated in response to the write request, to the update data as certification time-series information and that adds comparison time-series information to the updated parity data in association with the update data, the comparison time-series information having the same value as the certification time-series information; and a writing unit that distributes and writes, to the multiple storage devices, the update data to which the certification time-series information is added and the updated parity data to which the comparison time-series information is added.