Reconstructing data blocks in a raid array data storage system having storage device metadata and raid set metadata

摘要

A data block in a RAID array is reconstructed under the control of metadata recorded on the RAID array. The RAID array has a plurality of members, each member being a data storage device. The metadata includes device metadata for data blocks recorded on each member and RAIDset metadata for RAID protected data blocks recorded across the members of the RAID array. The RAID protected data blocks include user data blocks, RAIDset metadata blocks and parity data blocks. The data blocks are reconstructed by detecting from a device FE bit in the device metadata that a bad data block corresponding to or associated with the device FE bit needs to be reconstructed. The data is read from each data block, other than the bad data block, in the same RAID sliver with bad data block. A RAID sliver of data blocks includes all the data blocks in a RAID protected sliver of data blocks. From the data read from the other data blocks in the RAID sliver with the bad data block, the bad data block is regenerated to produce a new data block. The new data block is written in the RAID array as the reconstructed block in place of the bad data block. The device FE bit for the reconstructed data block is cleared to indicate the reconstructed data block is consistent with the other data blocks in the RAID protected sliver containing the reconstructed data block.