R&D: MAGIC, Making IMR Based HDD Perform Like CMR-Based HDD

IEEE Transactions on Computers has published an article written by Yuhong Liang, Computer Science and Engineering, The Chinese University of Hong Kong, 26451 Hong Kong, Hong Kong, Hong Kong, Ming-Chang Yang, Computer Science and Engineering, Chinese University of Hong Kong, 26451 New Territories, Hong Kong, Hong Kong, and Shuo-Han Chen, Institute of Information Science, Academia Sinica, 38017 Taipei, TW, Taiwan.

Abstract: “The past decades have witnessed the tremendous success of Conventional Magnetic Recording (CMR) based Hard Disk Drives (HDDs) in data storage. To eliminate the bottleneck of CMR based HDDs in providing higher areal density, an emerging Interlaced Magnetic Recording (IMR) is capable of achieving higher areal density with limited changes to disk makeup. Nevertheless, existing approaches for IMR based HDDs may suffer serious read and write performance degradation as compared with CMR based HDDs. Thus, this paper presents a device-level solution, namely MAGIC translation layer, which aims at MAkinG IMR based HDDs perform like CMR based HDDs in terms of comparable access performance. Specifically, not merely trying to improve the performance of raw IMR based HDDs, this work, for the first time, moves one step forward to minimize the performance gap between IMR and CMR based HDDs. Technically, by 1) fully utilizing two special CMR-like potentials of IMR and 2) gracefully trading the sequential access performance as space usage increases, MAGIC minimizes track rewriting overheads to achieve CMR-like performance. Our results reveal that MAGIC not only improves the write performance compared with existing designs, but also has potential to approach read and write performance of CMR based HDD.“