On Wed, Jul 07, 2010 at 03:34:01PM -0700, David Mathog wrote: > With "modern" hardware are there currently any notable instances where a > failed read of a hardware storage area block results in that missing > data being filled in with something other than null bytes?
Yes. You might get the wrong block due to a misdirected write or read, or you might get an old block because the previous write experienced "write tearing". If the OS knows it was unable to read a block and replaced it with zeros, it will throw an error. In Linux, the behavior depends on what you chose: panic on error, mount r/o, or continue. If the nulls are part of the filesystem metadata, all hell can break loose. The errors in the first paragraph won't be detected at all. They're rare, but... -- greg _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
