Parallels-related vm-rtc process running even when Parallels is not...

After shutting Parallels down, I notice that a process called vm-rtc keeps on running on my Ubuntu Edgy box, with top showing that it uses up 1% of CPU power (Opteron 165) at all times. The 'ps ax' command shows it as [vm-rtc], and it can't be killed. Related, I think, is that ifconfig shows the continued presence of an active NIC called vnic0 (IP 10.37.129.2), and route shows this as the destination for all 10.37.129.x addresses. Trying to take this interface down with 'sudo ifdown vnic0' fails because 'vnic0 is not configured'.

I can understand this with a Parallels VM (or the /usr/bin/parallels programme) still running... but afterwards? Why doesn't this interface come down after Parallels is through? What is this mysterious vm-rtc process?

 

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rtc = real time clock.
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