can you guess? wrote: > Ah - thanks to both of you. My own knowledge of video format internals is so > limited that I assumed most people here would be at least equally familiar > with the notion that a flipped bit or two in a video would hardly qualify as > any kind of disaster (or often even as being noticeable, unless one were > searching for it, in the case of commercial-quality video). >
But also, you're thinking like a consumer, not like an archivist. A bit lost in an achival video *is* a disaster, or at least a serious degradation. > David's comment about jpeg corruption would be more worrisome if it were > clear that any significant number of 'consumers' (the immediate subject of my > original comment in this area) had anything approaching 1 TB of jpegs on > their systems (which at an average of 1 MB per jpeg would be around a million > pictures...). If you include 'image files of various sorts', as he did > (though this also raises the question of whether we're still talking about > 'consumers'), then you also have to specify exactly how damaging single-bit > errors are to those various 'sorts' (one might guess not very for the > uncompressed formats that might well be taking up most of the space). And > since the CERN study seems to suggest that the vast majority of errors likely > to be encountered at this level of incidence (and which could be caught by > ZFS) are *detectable* errors, they'll (in the unlikely event that you > encounter them at all) typically only result in requiring use of a RAID (or > backup) copy (surel y > one wouldn't be entrusting data of any real value to a single disk). > They'll only be detected when the files are *read*; ZFS has the "scrub" concept, but most RAID systems don't, so the error could persist for years (and through generations of backups) before anybody noticed. > So I see no reason to change my suggestion that consumers just won't notice > the level of increased reliability that ZFS offers in this area: not only > would the difference be nearly invisible even if the systems they ran on were > otherwise perfect, but in the real world consumers have other reliability > issues to worry about that occur multiple orders of magnitude more frequently > than the kinds that ZFS protects against. > And yet I know many people who have lost data in ways that ZFS would have prevented. -- David Dyer-Bennet, [EMAIL PROTECTED]; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
