Re: [PATCH] Btrfs: do not create empty block group if we have allocated data

[Liu Bo <bo.li.liu@oracle.com>]

On Mon, Apr 11, 2016 at 05:02:18PM +0200, David Sterba wrote:
> On Mon, Dec 14, 2015 at 06:29:32PM -0800, Liu Bo wrote:
> > Now we force to create empty block group to keep data profile alive,
> > however, in the below example, we eventually get an empty block group
> > while we're trying to get more space for other types (metadata/system),
> > 
> > - Before,
> > block group "A": size=2G, used=1.2G
> > block group "B": size=2G, used=512M
> > 
> > - After "btrfs balance start -dusage=50 mount_point",
> > block group "A": size=2G, used=(1.2+0.5)G
> > block group "C": size=2G, used=0
> > 
> > Since there is no data in block group C, it won't be deleted
> > automatically and we have to get the unused 2G until the next mount.
> > 
> > Balance itself just moves data and doesn't remove data, so it's safe
> > to not create such a empty block group if we already have data
> >  allocated in other block groups.
> > 
> > Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
> 
> I'm adding the patch to my for-next.

Thank you, David.

Thanks,

-liubo