A New Decoding Algorithm for XOR-Based Erasure Codes

Data protection is essential in large-scale storage systems. Over the years, erasure codes, which provide the system ability to reconstruct data when damage occurs, have been proven effective and integrated within various large storage systems. With the emergence of new data storage technologies, such as SSD and NVMe [33, 34], the performance of erasure codes may soon become a potential bottleneck in the whole system. While encoding performance of XOR-based codes has been studied and optimized [7, 19, 20], there is a need of decoding performance to match. This paper addresses new methods in improving the decoding speed for XOR-based erasure codes. A new decoding algorithm is proposed, with which CPU cache can be utilized more efficiently. Various sets of experiments are conducted on different platforms, and the results show that, with the new decoding algorithm, general decoding speed gains considerable improvements.