That's awesome. I'm really looking forward to testing out RAID6.....raid5/6 is being rebased against the device replacement code. I'll have it posted this Friday along with a nice series of benchmarks.
Does anyone have any more information about this? Currently, when you tell btrfs to remove a drive, it rebalance the data first (by moving the data to other drives in the array). This takes a while with big/full disks, since the data has to be written. How is the new method different? Instead off moving data off of the old disk, and then back on to the new disk, does it simply produce new stripes on the new drive, and not bother copying anything off first? I'm curious about this, but couldn't find much info. Anyone know?In terms of line count, most of the code comes from Stefan, who added the ability to replace a single drive in place. This is different from how btrfs normally replaces drives, and is much much much faster.