MCB: a multidevice cooperative buffer management strategy for boosting the write performance of the SSD-SMR hybrid storage

Shingled magnetic recording (SMR) disks satisfy the growing demand for storage capacity for big data applications with their high capacity and low cost. However, the most severe challenge for SMR disks is the precipitous degradation of I/O performance when subjected to non-sequential writes. Using Solid State Drives (SSDs) as external caches for SMR disks is a cost-effective method to improve the I/O performance of SMR disks. Nevertheless, the existing SMR-oriented cache replacement algorithm is ineffective in resolving the conflict between the write amplification and the cache hit rate, resulting in limited performance gains from SSDs to SMR disks. In this paper, we design a multidevice cooperative buffer (MCB) management strategy to boost the write performance of SSD-SMR storage systems. Firstly, MCB selectively directs write traffic into the SSD cache to reduce the frequency of cleaning activity. Then, MCB adaptively evicts victim blocks from the SSD cache based on the locality principle. Finally, MCB utilizes a novelty SMR disk internal persistent buffer management mechanism to further optimize the efficiency of the SSD cache cleaning. The experimental results show that MCB achieves 7.4 × and 1.5 × performance improvements for write-intensive traces with spatial locality and temporal locality, respectively, compared to the state-of-the-art strategies.