Triple-Parity RAID and Beyond: As hard-drive capacities continue to outpace their throughput, the time has come for a new level of RAID.

Abstract

How much longer will current RAID techniques persevere? The RAID levels were codified in the late 1980s; double-parity RAID, known as RAID-6, is the current standard for high-availability, space-efficient storage. The incredible growth of hard-drive capacities, however, could impose serious limitations on the reliability even of RAID-6 systems. Recent trends in hard drives show that triple-parity RAID must soon become pervasive. In 2005, Scientific American reported on Kryder’s law, which predicts that hard-drive density will double annually. While the rate of doubling has not quite maintained that pace, it has been close.

References

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Index Terms

• General and reference

  • Document types

    • Surveys and overviews

• Hardware

  • Communication hardware, interfaces and storage

    • External storage

  • Integrated circuits

    • Semiconductor memory

      • Non-volatile memory