Reliability of XOR-based erasure codes on heterogeneous devices

Appeared in Proceedings of the 38th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN 2008).

Abstract

XOR-based erasure codes are a computationally-efficient means of generating redundancy in storage systems. Some such erasure codes provide irregular fault tolerance: some subsets of failed storage devices of a given size lead to data loss, whereas other subsets of failed storage devices of the same size are tolerated. Many storage systems are composed of heterogeneous devices that exhibit different failure and recovery rates, in which different placements— mappings of erasure-coded symbols to storage devices—of a flat XOR-based erasure code lead to different reliabilities. We have developed redundancy placement algorithms that utilize the structure of flat XOR-based erasure codes and a simple analytic model to determine placements that maximize reliability. Simulation studies validate the utility of the simple analytic reliability model and the efficacy of the redundancy placement algorithms.

Publication date:
June 2008

Authors:
Kevin Greenan
Ethan L. Miller
Jay Wylie

Projects:
Reliable Storage

Available media

Full paper text: PDF

Bibtex entry

@inproceedings{greenan-dsn08,
  author       = {Kevin Greenan and Ethan L. Miller and Jay Wylie},
  title        = {Reliability of {XOR}-based erasure codes on heterogeneous devices},
  booktitle    = {Proceedings of the 38th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN 2008)},
  pages        = {147-156},
  month        = jun,
  year         = {2008},
}