On 11/27/2012 6:37 AM, David Brown wrote: > To do checksumming (and in particular, recovery), requires higher level > knowledge of the data. The filesystem can track when it writes a file, > and update metadata (including, if desired, a data checksum) once it > knows the file is correctly stored. But I don't think it can sensibly > be done at the block device level - the recovery procedure doesn't know > what is old data, what is new data, or which bit is important to the > filesystem. > > So I think it can make sense to use a filesystem like ZFS or BTRFS that > can do checksumming - that is a reasonable level to add the checksum. You'll see CRC in XFS in the future as well. Some of the foundation is already laid to allow it, but IIRC it requires an on disk format change for full implementation. On disk format changes are a big deal and are taken with great care. IIRC XFS has only seen one or two in 18 years. -- Stan -- 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
