On December 13, 2007 12:51:55 PM -0800 "can you guess?" <[EMAIL PROTECTED]> wrote: > ... > >> when the difference between an unrecoverable single >> bit error is not just >> 1 bit but the entire file, or corruption of an entire >> database row (etc), >> those small and infrequent errors are an "extremely >> big" deal. > > You are confusing unrecoverable disk errors (which are rare but orders of > magnitude more common) with otherwise *undetectable* errors (the > occurrence of which is at most once in petabytes by the studies I've > seen, rather than once in terabytes), despite my attempt to delineate the > difference clearly.
No I'm not. I know exactly what you are talking about. > Conventional approaches using scrubbing provide as > complete protection against unrecoverable disk errors as ZFS does: it's > only the far rarer otherwise *undetectable* errors that ZFS catches and > they don't. yes. far rarer and yet home users still see them. that the home user ever sees these extremely rare (undetectable) errors may have more to do with poor connection (cables, etc) to the disk, and less to do with disk media errors. enterprise users probably have better connectivity and see errors due to high i/o. just thinking out loud. regardless, zfs on non-raid provides better protection than zfs on raid (well, depending on raid configuration) so just from the data integrity POV non-raid would generally be preferred. the fact that the type of error being prevented is rare doesn't change that and i was further arguing that even though it's rare the impact can be high so you don't want to write it off. -frank _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
