Yes, stolen time happens in most moderns systems as a result of power
management (and you can probably count SMM cycles as stolen if only
there was a way to count them). It would be useful to report on a
laptop, for instance, how many cycles have been stolen by running off
battery or on a server because of heat issues. Having an interface for
Linux to report this seems useful. It is a covert channel, however, in
a virtualized environment, so there should be some provision in the
hypervisor to turn it off.
Zach
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