discrepancies in used space after cpio

[Dmitry Morozovsky]

On Mon, 18 May 2009, Paul Wootton wrote:

PW> > > I am currently in the process of moving all my data around, going from a
PW> > > single zfs drive (ex-mirror) to a zfs raidz.
PW> > > I have used cpio to copy the data to the new pool, but a du shows a big
PW> > > difference in the results.
PW> > > 
PW> > > Does anyone have any ideas, or does a "du -h ." not do what I think it
PW> > > should?
PW> > >     
PW> > it is a known bug (at least for the solaris folks) that du does not
PW> > display disk usage correctly on raidz.
PW> > 
PW> > But of course different compression algorithms come into play as well.
PW> >   
PW> In this instance, the du from the raidz pool is actually correct.
PW> A zfs list shows less space (incorrect) on the single drive compared to the
PW> raidz.
PW> Doing a tar on both directories gives  2 1.2G files so the data is actually
PW> present on both packs (plus I used CPIO to copy the data from the single to
PW> the raidz)
PW> 
PW> Is it possible for data corruption on the single drive to not show the extra
PW> space as being used?

Ehmm, possibly stupid question: sparse files?

-- 
Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
[ FreeBSD committer:                                 marck at FreeBSD.org ]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at rinet.ru ***
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