Does your application depend on, or report, free disk space? Re: F20 Self Contained Change: OS Installer Support for LVM Thin Provisioning

[Richard W.M. Jones]

On Mon, Jul 29, 2013 at 08:01:23AM -0600, Chris Murphy wrote:
> 
> On Jul 29, 2013, at 6:30 AM, "Daniel P. Berrange" <berrange at redhat.com> wrote:
> 
> > Yep, we need to be able to report free space on filesystems, so that
> > apps provisioning virtual machines can get an idea of how much storage
> > they can provide to VMs without risk of over comitting.
> > 
> > I agree that we really want the kernel, or at least a reusable shared
> > library, to provide some kind of interface to determine this, rather
> > than requiring every userspace app which cares to re-invent the wheel.
>
> What does it mean for an app to use stat to get free space, and then
> proceeds to create too big a VM image in a directory that has a
> quota set? I still think apps are asking an
> inappropriate/unqualified question by asking for volume free space,
> instead of what's available to them for a specified path.

libvirt only does what users (or applications) ask of it.

The problem is that the information is not available to give to users/
applications so they can make a good decision.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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