On Tue, Jun 26, 2012 at 3:46 AM, H. Peter Anvin <hpa@xxxxxxxxx> wrote: > > On 06/25/2012 08:21 AM, Chris Mason wrote: > > Yes and no. If you have 2 drives and you add one more, we can make it > > do all new chunks over 3 drives. But, turning the existing double > > mirror chunks into a triple mirror requires a balance. > > > > -chris > > So trigger one. This is the exact analogue to the resync pass that is > required in classic RAID after adding new media. > > -hpa > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html To me one doesn't have to be triggered, a user expects to have to tell the disks to rebuild/resync/balance after adding a disk, they may want to wait till they've added all 4 disks and run a few extra commands before they run the rebalance. What is important is having a mode that doesn't require the user to remember that what they had used as the closest analogue to RAID1 that BTRFS supports requires them to run another command to change the 'RAID level' to be the RAID1 analogue for the new number of disks. Users will forget that and they will lose data because of it. At least with a M=N mode BTRFS can say they tried to make it easy to avoid that pitfall. (resend in plain text for mailing list, CC list received the HTML version) -- Gareth Pye Level 2 Judge, Melbourne, Australia Australian MTG Forum: mtgau.com gareth@xxxxxxxxxxxxxx - www.rockpaperdynamite.wordpress.com "Dear God, I would like to file a bug report" -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
