From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alessandro Sardo <sandro.sardo@polito.it>
Subject: Migration of paused domains
Date: Sat, 19 Jul 2008 14:33:48 +0200
Message-ID: <4881DF2C.4080806@polito.it>
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Hello,

today I wanted to find out if it was possible to migrate a paused 
domain. So, I tried the following:

# xm pause <dom>
# xm migrate <dom> <dest>

Unfortunately, the migration process would just hang before suspending 
the domain and transferring its state. In order to resume it and 
complete migration, I had to unpause the domain:

# xm unpause <dom>

After that, the process did get completed successfully.

-----

Then, I tried and track down the reason of this in the sources, and I 
came to the following snip (XendDomainInfo.py):

def waitForShutdown(self):
      self.state_updated.acquire()
           try:
                while self._stateGet() in 
(DOM_STATE_RUNNING,DOM_STATE_PAUSED):
                self.state_updated.wait()
           finally:
                self.state_updated.release()

It looks like that makes it wait forever, since the domain remains stuck 
in the DOM_STATE_PAUSED state.

Now, the question is: is that the right behaviour or am I missing 
something? Is it really not possible to migrate a paused domain?

Thanks,

- AS