Re: [Libguestfs] performance between guestfish and qemu-nbd
On Fri, Jul 28, 2017 at 12:23:04AM +0800, lampahome wrote:
2017-07-27 20:18 GMT+08:00 Richard W.M. Jones
<rjones(a)redhat.com>:
> On Thu, Jul 27, 2017 at 06:34:13PM +0800, lampahome wrote:
> > I can mount qcow2 img to nbd devices through guestfish or qemu-nbd
> >
> > I'm curious about which performance is better?
>
> They do quite different things, they're not comparable.
>
> Can you specifically give the commands you are trying? We might be
> able to give more sensible advice.
guestfish:
guestfish --rw -a demo.qcow2 -m /dev/nbd0
qemu-nbd:
qemu-nbd -c /dev/nbd0 demo.qcow2
These don't do the same thing. In fact the guestfish command doesn't
work at all.
I just want to mount demo.qcow2 to a device
Still unclear.
You want to export demo.qcow2 as NBD? Use qemu-nbd.
You want to mount demo.qcow2 on the local filesystem? (This doesn't
involve NBD.) Use:
mkdir /tmp/mnt
guestmount --rw -a demo.qcow2 -i /tmp/mnt
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine. Supports Linux and Windows.
http://people.redhat.com/~rjones/virt-df/