Re: delalloc fragmenting files?

[Eric Sandeen <sandeen@redhat.com>]

Andreas Dilger wrote:

> On a related note - the FIEMAP patches to filefrag also include a new
> output format that is much more useful, IMHO.  The new format is like:
> 
> {filename}
> ext: [logical start.. end kB]: phys start..end kB    :           kB:lun: flags
>   0: [         0..     30207]:     401416..    522251:       120828: 0 :
>   1: [     30208..     60927]:     532480..    655359:       122880: 0 :
>   2: [     60928..    121855]:     790536..    916484:       125948: 0 :
> 
> Hopefully Kalpak will be able to post the updated patches here soon.

yep, I hacked existing filefrag to do something like this, the existing
format is pretty hard to glance over :)

One thing I like about xfs_bmap is that it can tell you which Allocation
Group the blocks are in; most filesystems have some concept of
sub-regions of the filesystem, such as BGs or resource groups or whatnot
- do you think there is room for this in the FIEMAP interface?  Hm, or
should this just be calculated from knowing the size of the sub-regions...

-Eric