On 10/19/11 03:12 AM, Paul Kraus wrote:
On Tue, Oct 18, 2011 at 9:13 AM, Darren J Moffat
<darr...@opensolaris.org>  wrote:
On 10/18/11 14:04, Jim Klimov wrote:
2011-10-18 16:26, Darren J Moffat пишет:
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()


http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs/zfs/metaslab.c


See lines 1356-1378

And the admin interface would be what exactly?..
As I said there isn't one because that isn't how it works today it is all
automatic and only for new writes.

I was pointing out that ZFS does do 'something' not that it had an exactly
matching feature.
I have done a "poor man's" rebalance by copying data after adding
devices. I know this is not a substitute for a real online rebalance,
but it gets the job done (if you can take the data offline, I do it a
small chunk at a time).

I do the same.

Whether you do the balance by hand, or the filesystem does it the data still has to be moved around which can be resource intensive. I'd rather do that at a time of my choosing.

--
Ian.

_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

Reply via email to