| | |
Summary: IRON File Systems
Vijayan Prabhakaran, Lakshmi N. Bairavasundaram, Nitin Agrawal, Haryadi S. Gunawi,
Andrea C. ArpaciDusseau, and Remzi H. ArpaciDusseau
Computer Sciences Department, University of Wisconsin, Madison
{vijayan,laksh,nitina,haryadi,dusseau,remzi}@cs.wisc.edu
ABSTRACT
Commodity file systems trust disks to either work or fail com
pletely, yet modern disks exhibit more complex failure modes. We
suggest a new failpartial failure model for disks, which incorpo
rates realistic localized faults such as latent sector errors and block
corruption. We then develop and apply a novel failurepolicy fin
gerprinting framework, to investigate how commodity file systems
react to a range of more realistic disk failures. We classify their
failure policies in a new taxonomy that measures their Internal RO
bustNess (IRON), which includes both failure detection and recov
ery techniques. We show that commodity file system failure poli
cies are often inconsistent, sometimes buggy, and generally inade
quate in their ability to recover from partial disk failures. Finally,
we design, implement, and evaluate a prototype IRON file system,
Linux ixt3, showing that techniques such as indisk checksumming,
|