[Libguestfs] Plan for libguestfs 1.28

[Richard W.M. Jones]

[Please keep replies on the list to help others]

On Fri, Oct 10, 2014 at 05:01:22PM +0800, Zhi Yong Wu wrote:
> On Fri, Oct 10, 2014 at 4:47 PM, Richard W.M. Jones <rjones at redhat.com> wrote:
> > On Fri, Oct 10, 2014 at 04:26:20PM +0800, Zhi Yong Wu wrote:
> >> You can't make sure that guest never fail or panic forever, right?
> >
> > Do you mean the guest or the libguestfs appliance?
> >
> >> That is, you will have to maintain that guest, not customers' guests.
> >> This risk is beyond thought. The maintainance cost will be very
> >> expensive in our super large scale cloud environment.
> >>
> >> We are trying not to start a appliance guest when issuing a libguestfs
> >> command, such as virt-resize.
> >
> > There may be some confusion here.  Virt-resize doesn't run the guest.
> When i issue virt-resize, i exactly saw one guest is started, indisk
> and outdisk are attached to this guest....
> 
> Do you mean that in the latest upstream, virt-resize doesn't run the guest?

OK so you mean the libguestfs appliance.

> > TBH I'm not exactly sure what your concerns are.
>
> We are afraid that if a guest is started when vrit-xxx command is
> issued, it will bring some unexpected risks and take too much time to
> complete this command.

If you have any concrete problems, then let us know.

You may wish to limit the number of virt-resize processes than can run
at any one time.  GNU 'sem' can do this relatively easily:

  https://www.gnu.org/software/parallel/sem.html

There are various tips on how to manage the appliance discussed in
this manual page:

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

Rich.

-- 
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