[libvirt] Re: [Qemu-devel] [PATCH 1/6] Allow multiple monitor devices (v2)

Anthony Liguori aliguori at us.ibm.com
Mon May 11 21:51:59 UTC 2009

Hollis Blanchard wrote:
> On Wed, 2009-04-08 at 13:34 -0500, Anthony Liguori wrote:
>> Right now only one monitor device can be enabled at a time.  In order to support
>> asynchronous notification of events, I would like to introduce a 'wait' command
>> that waits for an event to occur.  This implies that we need an additional
>> monitor session to allow commands to still be executed while waiting for an
>> asynchronous notification.
> Was there any consensus reached in this thread? I'm once again looking
> for ways to communicate qemu watchdog events to libvirt.

We can do multiple monitors as a debugging tool, but to support events, 
a proper machine monitor mode is a prerequisite.

The real requirement is that events are obtainable via a single 
communication channel instead of requiring two separate communication 
channels.  Internal implementation will look at lot like these patches.

The reasoning for requiring a single channel is that coordinating 
between the two channels is expected to be prohibitively difficult.  To 
have a single channel, we need a machine mode.  It cannot be done in a 
human readable fashion.

I think this summarizes the consensus we reached.  I don't agree fully 
with the above but I'm okay with it.  Would you agree Avi?


Anthony Liguori

More information about the libvir-list mailing list