Idle Read After Write - IRAW

Despite a low occurrence rate, silent data corruption represents a growing concern for storage systems designers. Throughout the storage hierarchy, from the file system down to the disk drives, various solutions exist to avoid, detect, and correct silent data corruption. Undetected errors during the completion of WRITEs may cause silent data corruption. A portion of the WRITE errors may be detected and corrected successfully by verifying the data written on the disk with the data in the disk cache. Write verification traditionally is scheduled immediately after a WRITE completion (Read After Write - RAW) which is unattractive, because it degrades user performance. To reduce the performance penalty associated with RAW, we propose to retain the written content in the disk cache and verify it once the disk drive becomes idle. Although attractive, this approach (called IRAW Idle Read After Write) contends for resources, i.e., cache and idle time, with user traffic and other background act...

• Type: Conference
• Year: 2008
• Where: USENIX
• Authors: Alma Riska, Erik Riedel
• Keywords: Disk Cache, Disk Drives, Operating System, Silent Data Corruption, USENIX 2008