The RAID-6 configuration is more tolerant of disk failures than other RAID levels because of its ability to tolerate two disk failures. However, previous RAID-6 codes suffer from two major overheads - the time of encoding or decoding processes plus the need to access multiple blocks when updating parities or recovering failed blocks. For example, the PS and Reed-Solomon codes do not have optimal computation complexity, while P-code, X-code and RDP-code must access multiple blocks to update parities during write operations. This work proposes a new XOR- based RAID-6 code, called Tier-code, which not only achieves the optimal parity computation complexity, but also increases the write and degraded-mode read performance compared to previous codes. It uses two tiers of coding, one at the block level and the other at the chunk level. Experimental results of software testing, simulation and ASIC synthesis for this new hierarchical code demonstrate that Tier-code can outperform the previous RAID-6 codes in both write performance and degraded-mode read performance while maintaining the optimal computation complexity in both hardware and software implementations.
|Original language||English (US)|
|Title of host publication||2018 IEEE International Conference on Networking, Architecture and Storage, NAS 2018 - Proceedings|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|State||Published - Oct 30 2018|
|Event||13th IEEE International Conference on Networking, Architecture and Storage, NAS 2018 - Chongqing, China|
Duration: Oct 11 2018 → Oct 14 2018
|Name||2018 IEEE International Conference on Networking, Architecture and Storage, NAS 2018 - Proceedings|
|Other||13th IEEE International Conference on Networking, Architecture and Storage, NAS 2018|
|Period||10/11/18 → 10/14/18|
Bibliographical noteFunding Information:
This work was supported in part by the Center for Research in Intelligent Storage (CRIS), which is supported by National Science Foundation grant no. IIP-1439622 and member companies. The work of S. Mohajer is supported in part by the National Science Foundation under Grant CCF-1617884. Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the NSF.