TestBot: A dive into the Windows timers

[Henri Verbeet]

I guess the first step would be to figure out what timer source
Windows actually ends up using. As the configuration snippet shows,
there are a couple of options it can choose from. (I seem to recall
there was a way to figure this out, but don't recall from the top of
my head.)

I've read claims that compared to earlier versions Windows 10 will
prefer the TSC over the HPET because it has better latency, but that
that may not be the best choice for VMs. I also notice "hypervclock"
in the configuration snippet above; I suspect Windows 10 will prefer
that one if it's present, but I have no idea how stable that clock is.