Time in computing represents a resource with quite particular
characteristics. It has a unique, irreversible direction and passes
regularly, meaning that its state changes without interference. Today's
systems usually consist of several time sources, which measure passage of
time since system boot independently from each other. The attempt to
virtualize any of those must not contradict the characteristics of time.
Yet no sophisticated hardware or software solutions are available for
virtualization environments. The issue here is that a virtual machine can
be preempted at any point in time. This work presents an approach to virtualize
time in a manner that does not invalidate what an operating system assumes. In
spite of preemptions a virtual machine shall observe time passing with the
same characteristics as it would when running on bare metal.
Time Virtualization in NOVA and Vancouver
Verteidigung der Belegarbeit