Re: [dm-devel] [PATCH 1/2] dm-kcopyd: introduce per-module throttle structure

[Joe Thornber <thornber redhat com>]

On Fri, Jun 10, 2011 at 09:41:50AM -0400, Mikulas Patocka wrote:
> This works if the data is directly on the partition, but it won't work on 
> the device mapper (if MD is on the device mapper, it won't work too).
> 
> The device mapper has no function to tell where the bio is finally 
> remapped, so you can't read disk statistics for that particular disk.

ok, thx