On 10/18/11 13:18, Edward Ned Harvey wrote:
* btrfs is able to balance. (after adding new blank devices, rebalance, so
the data& workload are distributed across all the devices.) zfs is not
able to do this yet.
ZFS does slightly biases new vdevs for new writes so that we will get to
a more even spread. It doesn't go and move already written blocks onto
the new vdevs though. So while there isn't an admin interface to
rebalancing ZFS does do something in this area.
This is implemented in metaslab_alloc_dva()
See lines 1356-1378
Darren J Moffat
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