Research on efficient triple disk failure tolerance data placement scheme based on parity code
基于奇偶校验的三容错数据布局研究

The data placement scheme based on single-erasure correcting codes can not satisfy the requirement of storage system on reliability. Now there are more and more researches on the data placement scheme based on multi-erasure correcting codes such as HDD1, HDD2. But these data placement schemes have some disadvantages such as poor redundancy, heavy computing load. A data placement scheme based on triple parity was designed, which can tolerance three disk errors. It adds two parity disks into a RAID5 disk array system, and uses the horizontal parity, diagonal parity and anti-diagonal parity to correct error. The encoding and decoding algorithm of the data placement scheme is simple, the length of parity stripe is equal in triple parity, computing load is light, and easy to implement. In addition, the performance of this scheme in small writes improves obvious comparing with other multi-erasure correcting data placement schemes, for decreasing the logical relationship among triple parity.