On Nov 27, 2012, at 12:27 PM, Roy Sigurd Karlsbakk <roy@xxxxxxxxxxxxx> wrote: > ----- Opprinnelig melding ----- >> On Nov 27, 2012, at 6:05 AM, David Brown <david.brown@xxxxxxxxxxxx> >> wrote: >>> >>> It is /undetected/ disk errors that are a problem. Typical figures I >>> have seen are around 1 in 1e12 4KB blocks - or 1 in 3e16 bits. >> >> Is this with consumer SATA? Or other? > > According to a few studies I've read, the number of silent errors are identical on both consumer SATA drives and SAS drives. It's the density that makes errors, and the platters and disk heads are produced alike. That's not what I'm reading: Corruption detected in 8.5% of nearline disks, and 1.9% in enterprise disks. http://www.pdsi-scidac.org/events/PDSW09/resources/pdsw09_slides13.pdf In this study it's 0.86% of nearline, and 0.065% of enterprise disks developing checksum mismatches, out of 1.53 million disks. http://static.usenix.org/event/fast08/tech/full_papers/bairavasundaram/bairavasundaram.pdf The ratios are the same. Chris Murphy-- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
