It is well known that erasure coding can be used in storage systems to efficiently store data while protecting against failures.Conventionally,the design of erasure codes has focused on the tradeoff between redundancy and reliability.Under this criterion,an maximum distance separable(MDS) code has optimal redundancy.In this paper,we address a new class of MDS array codes for tolerating triple node failures by extending the row diagonal parity(RDP) code,named the RDDP(row double diagonal parity) code.The RDDP code takes advantages of good performances of the RDP code with balanced I/O.A specific triple-erasure decoding algorithm to reduce decoding complexity is depicted by geometric graph,and it is easily implemented by software and hardware.The theoretical analysis shows that the comprehensive properties of the RDDP code are optimal,such as encoding and decoding efficiency,update efficiency and I/O balance performance. It is well known that erasure coding can be used in storage systems to efficiently store data while protecting against failures. Conventionally, the design of erasure codes has focused on the tradeoff between redundancy and reliability. Under this criterion, an maximum distance separable (MDS) code has optimal redundancy. In this paper, we address a new class of MDS array codes for tolerating triple node failures by extending the row diagonal parity (RDP) code, named the RDDP (row double diagonal parity) code. of good performances of the RDP code with balanced I / OA specific triple-erasure decoding algorithm to reduce decoding complexity is depicted by geometric graph, and it is easily implemented by software and hardware. The theoretical analysis shows that the comprehensive properties of the RDDP code are optimal, such as encoding and decoding efficiency, update efficiency and I / O balance performance.