RAID Level 6 and Level 6+ Reliability

Thomas Johannes Emil Schwarz


Storage systems are built of fallible components but have to provide high degrees of reliability. Besides mirroring and triplicating data, redundant storage of information using erasure-correcting codes is the only possibility to have data survive device failure.We provide here exact formula for the data-loss probability of a disk array composed of several RAID Level 6 stripes. This two-failure tolerant is not only used in practice but can also provide a reference point for the assessment of other data organizations.

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Lakshmi Bairavasundaram, Garth Goodson, Shankar Pasupathy, and Jiri Schindler. An analysis of latent sector errors in disk drives. In SIGMETRICS Performance Evaluation Review, Vol. 35(1). ACM, 289300. (2007).

Mario Blaum, Jim Brady, Jehoshua Bruck, and Jai Menon: "EVENODD: An efficient scheme for tolerating double disk failures in RAID architectures." IEEE Transactions on computers 44.2, p.192-202, (1992).

Peter Chen, Edward Lee, Garth Gibson, Randy Katz, and David Patterson. "RAID: High-performance, reliable secondary storage." ACM Computing Surveys (CSUR) vol. 26, no. 2, p. 145-185. (1992).

Ajay Dholakia, Evangelos Eleftheriou, Xiao-Yu Hu, Ilias Iliadis, Jai Menon, and K. K. Rao. "A new intra-disk redundancy scheme for high-reliability RAID storage systems in the presence of unrecoverable errors." ACM Transactions on Storage (TOS) 4, no. 1 pp. 1-42, (2008).

Jon Elerath and Michael Pecht. "A highly accurate method for assessing reliability of redundant arrays of inexpensive disks (RAID)." IEEE Transactions on Computers 58, no. 3 (2008): 289-299.

Jim Gray, personal communication.

Mark Holland and Garth A. Gibson. "Parity declustering for continuous operation in redundant disk arrays." ACM SIGPLAN Notices 27, no. 9, 1992, p.23-35 / Proceedings of ASPLOS 92.

Jehan-Franois Pris, Ahmed Amer, and Thomas Schwarz. "Low-redundancy two-dimensional RAID arrays." In 2012 International Conference on Computing, Networking and Communications (ICNC), pp. 507-511. IEEE, (2012).

Bianca Schroeder, Sotirios Damouras, and Phillipa Gill: Understanding latent sector errors and how to protect against them. ACM Transactions on Storage (TOS) 6, 3 (2010).

Bianca Schroeder and Garth A. Gibson. "Understanding disk failure rates: What does an MTTF of 1,000,000 hours mean to you?" ACM Transactions on Storage (TOS) 3, no. 3 , 2007.

Thomas Schwarz and Walter Burkhard, Reliability and performance of RAIDs. IEEE Transactions on Magnetics, 31(2), pp.1161-1166, (1995).

Qin Xin, Q., Thomas Schwarz, and Ethan Miller. September. Disk infant mortality in large storage systems. In 13th IEEE International Symposium on Modeling, Analysis, and Simulation of Computer and Telecommunication Systems (pp. 125-134), 2005.


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