xfs and actual percentage diskfree

[joost@snow.nl]

ls,

As part of an installation process I create a new XFS filesystem and I
copy approx. 557MB to a 660MB filesystem using cpio -pdm.

During this copy-process I see the diskusage as reported by df grow to
100%, also indicating lots of ups-and-downs of diskusage and related
percentage of free diskspace.

In the end I manage to copy no more than approx. 550 MB to the
filesystem, as it becomes 100% full with cpio reporting: no more space
left on device.

After waiting for 10 minutes, df reports an astonishing 85% in use!

My questions are:
1) is this a bug?
2) how can I avoid this behaviour (mkfs option, mount option,
   xfs_admin action)

my current solution (hack the list of files in 40 pieces and put
a sleep 10 in between 40 cpio statements) works fine, although for 85%
use in the end, the file-system goes up to 91%, so the 10 second sleep
ought to be more.

the file-system I create is dd-ed onto the final installation media
and xfs-growed into the partition size, so any mkfs-option to avoid
this behaviour may end up in the target file-system as well. that may
be undesireable.

Thanks for any help,

Joost Helbert, CTO Snow B.V.

PS: linux-2.4.18 with xfs patches and xfsprogs-2.0.3.src are used in
    this case.
PPS: maillist-archives didn't show anything related.

-- 
Joost Helberg
Technisch Directeur Snow BV http://snow.nl Tel 0418-653333 Fax 0418-653666
Voorzitter VOSN         http://www.vosn.nl Tel 0418-653336 Fax 0418-653666
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