[Gluster-users] Renaming a file in a distributed volume

[Marcelo Roccasalva]

On Sat, Oct 13, 2012 at 1:53 PM, Brian Candler <B.Candler at pobox.com> wrote:
>
> On Sat, Oct 13, 2012 at 05:05:08PM +0200, Stephan von Krawczynski wrote:
> > On Sat, 13 Oct 2012 15:52:56 +0100
> > Brian Candler <B.Candler at pobox.com> wrote:
> >
> > > In a distributed volume (glusterfs 3.3), files within a directory are
> > > assigned to a brick by a hash of their filename, correct?
> > >
> > > So what happens if you do "mv foo bar"? Does the file get copied to another
> > > brick? Is this no longer an atomic operation?
> > >
> > > Thanks,
> > >
> > > Brian.
> >
> > In fact it has never been atomic.
> > Take a look at my corresponding bug report from "back then"...
> > You can use a small script to show it is not.
>
> I hunted around, I couldn't find much in bugzilla apart from
> https://bugzilla.redhat.com/show_bug.cgi?id=762766
> (seems to be more about replicated volumes). I couldn't find any bugs
> containing "skraw", but I'm probably just driving bugzilla wrongly.
>
> I did find this recent posting though:
> http://permalink.gmane.org/gmane.comp.file-systems.gluster.devel/2888
> Is this what you're talking about? This is about an old version of glusterfs
> but the version used is not specified as far as I can see.
>
> Anyway, I think my question is answered. Normally I would create a file as
> xxx.tmp, sync and then rename it to xxx, to protect against a
> partially-created file; but for large files this looks like it's not a good
> approach for glusterfs with a distributed volume.

So are some tools like winscp or rsync which use temporary names mostly...

--
Marcelo

"¿No será acaso que esta vida moderna está teniendo más de moderna que
de vida?" (Mafalda)