Re: Why QCOW1?

[Kevin Wolf <kwolf@redhat.com>]

Am 15.04.2011 14:05, schrieb Stefan Hajnoczi:
> On Fri, Apr 15, 2011 at 12:17 PM, Pekka Enberg <penberg@kernel.org> wrote:
>> On Fri, Apr 15, 2011 at 1:14 PM, Stefan Hajnoczi <stefanha@gmail.com> wrote:
>>> Why even use a non-raw image format?  The current implementation only
>>> does sparse files, but POSIX sparse raw files gives you the same
>>> feature.
>>
>> Because people have existing images they want to boot to?
> 
> People don't have existing QCOW1 images they want to boot from :).
> 
> They have vmdk, vhd, vdi, or qcow2.  You can use qemu-img to convert
> them to raw.  You can use qemu-nbd if you are desperate to boot from
> or inspect them in-place.
> 
> But I think the natural path for a native Linux KVM tool is to fully
> exploit file systems and block layer features in Linux instead of
> implementing a userspace block layer.

As a normal user, I can deal with files, but I can't write to block
devices or mount file systems. I'm sure that there are use cases that
don't require file-based formats, but I'm also relatively sure that they
are a minority (at least if you also take convenience into consideration).

Kevin