http://www.cs.wisc.edu/adsl/Publications/corruption-fast08.html
Page 13 of the above paper says: # Figure 12 presents for each block number, the number of disk drives of disk # model ‘E-1’ that developed a checksum mismatch at that block number. We see # in the figure that many disks develop corruption for a specific set of block # numbers. We also verified that (i) other disk models did not develop # multiple check-sum mismatches for the same set of block numbers (ii) the # disks that developed mismatches at the same block numbers belong to # different storage systems, and (iii) our software stack has no specific data # structure that is placed at the block numbers of interest. # # These observations indicate that hardware or firmware bugs that affect # specific sets of block numbers might exist. Therefore, RAID system designers # may be well-advised to use staggered stripes such that the blocks that form # a stripe (providing the required redundancy) are placed at different block # numbers on different disks. Does the BTRFS RAID functionality do such staggered stripes? If not could it be added? I guess there's nothing stopping a sysadmin from allocating an unused partition at the start of each disk and use a different size for each disk. But I think it would be best to do this inside the filesystem. Also this is another reason for having DUP+RAID-1. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
