[Libguestfs] Why libguestfs guest exist exceptionally?

[Richard W.M. Jones]

On Mon, Sep 29, 2014 at 12:55:04AM +0800, Zhi Yong Wu wrote:
> On Mon, Sep 29, 2014 at 12:36 AM, Richard W.M. Jones <rjones at redhat.com> wrote:
> > On Sun, Sep 28, 2014 at 11:43:17PM +0800, Zhi Yong Wu wrote:
> >> Yeah, but why did it happen when i directly issue guest VM via above command?
> >
> > OK I see.  When libguestfs runs qemu-kvm, it sets up a TCP socket
> > first [on RHEL 5 -- it works differently upstream].  Without the
> > socket existing (and sending commands etc), the qemu-kvm command on
> > its own won't work.
> I got it, thanks.
> 
> By the way, i found that virt-xxx usually has very poor performance on
> my box. e.g. virt-filesystems will return the result in 30s,
> virt-resize will need 30 minutes to complete resizing one disk. Every
> virt-xxx need to start one QEMU guest at first every time it is
> issued, so this takes too long time to run. I am trying to find out
> some ways to improve its perf.

A good place to start is:

  http://libguestfs.org/guestfs-performance.1.html

Are you running this inside a VM?

Rich.

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