On Mon, 1 Dec 2014, Chris Murphy <li...@colorremedies.com> wrote: > On Sun, Nov 30, 2014 at 3:06 PM, Russell Coker <russ...@coker.com.au> wrote: > > When the 2 disks have different data mdadm has no way of knowing which > > one is correct and has a 50% chance of overwriting good data. But BTRFS > > does checksums on all reads and solves the problem of corrupt data - as > > long as you don't have 2 corrupt sectors in matching blocks. > > Yeah. I'm not sure though if openSUSE 13.2 prevents users from > creating btrfs raid1 volumes entirely, or if it's just an install time > limitation.
With BTRFS you can make it RAID-1 afterwards. The possibility of data loss during system install usually isn't something you are concerned about so this shouldn't be a problem. > I know that Fedora's installer won't allow the user to create Btrfs on > LVM, and it probably doesn't allow it on md raid either. For LVM that's reasonable, for MD-RAID that would be a bug IMHO. On Mon, 1 Dec 2014, Roman Mamedov <r...@romanrm.net> wrote: > * mdadm RAID has much better read balancing; > Btrfs reads are satisfied from what's in effect a random drive > (PID-based balancing of threads to drives), mdadm reads from the > less-loaded drive. Also mdadm has a way to specify some RAID1 array > members as to be never used for reads if at all possible ("write-mostly"), > which helps in RAID1 of HDD and SSD. True. But that's just a lack of performance tuning in the current code, it will be fixed at some future time. -- 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html