[virt-tools-list] Storage image files and permissions

Vincenzo Romano vincenzo.romano at notorand.it
Tue Nov 27 16:03:32 UTC 2018


Il giorno mar 27 nov 2018 alle ore 16:37 Joachim Wagner
<jwagner at computing.dcu.ie> ha scritto:
>
> > > > Moreover, I created a QCOW3 disk image. I asked for a maximum capacity
> > > > of 6GB and initial allocation of 0GB (zero).
> > > > I got a 6GB image file. Is this a bug or am I missing something?
> >
> > Any hint on this?
> > With QCOW2 I used to get a 200KB file as initial image, no matter it's
> > maximum size.
>
> Have you checked the space used on disk or the file size? Possibly, the
> default on your system is to use sparse pre-allocation when supported by the
> filesystem.

You are right! The 'du' tool is showing that it's not eating 6GB but just 2.

> Also, did you try preallocation=off or metadata (see man page)?

I have used the GUI from virt-manager and chose a maximum allocation
of 6GB and an initial allocation of 0GB.

> How do you request qcow3? According to the edit history of https://
> wiki.qemu.org/Features/Qcow3 , qcow3 should be many years old but the manpage
> of qemu-img on my current system does not mention qcow3.

I didn't request it. The virt-manager let me chose qcow3 against raw.
That's it.

>
> Joachim
-- 
Vincenzo Romano - NotOrAnd.IT
Information Technologies
--
NON QVIETIS MARIBVS NAVTA PERITVS




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