FAST '08 – Abstract
Pp. 97–110 of the Proceedings
The RAID-6 Liberation Codes
James S. Plank, University of Tennessee
The RAID-6 specification calls for a storage system with multiple
storage devices to tolerate the failure of any two devices. Numerous
erasure coding techniques have been developed that can implement
RAID-6; however, each has limitations. In this paper, we describe a
new class of RAID-6 codes called the Liberation Codes. These
codes encode, update and decode either optimally or close to
optimally. Their modification overhead is lower than all other
RAID-6 codes, and their encoding performance is often better as well.
We provide an exact specification of the Liberation Codes and assess
their performance in relation to other RAID-6 coding techniques. In
the process, we describe an algorithm called bit matrix
scheduling, which improves the performance of decoding drastically.
Finally, we present a freely available library which facilitates the
use of Liberation Codes in RAID-6 sytems.
- View the full text of this paper in HTML and PDF.
Listen to the presentation in
The Proceedings are published as a collective work, © 2008 by the USENIX Association. All Rights Reserved. Rights to individual papers remain with the author or the author's employer. Permission is granted for the noncommercial reproduction of the complete work for educational or research purposes. USENIX acknowledges all trademarks within this paper.