[coyotos-dev] sleep capability

[Eric Northup]

Jonathan S. Shapiro wrote:
[...]

> 2. Running a second thread on a concurrent CPU is good enough to get a
> very high accuracy clock. With most modern CPUs being multithread or
> multicore, this means that disabling RDTSC will not help. Further, a
> shared page is sufficient to provide highly accurate run-in information
> under these conditions.
> 
> Given (2), the only real solution is a deterministic scheduler. The
> problem with this is that real users will not accept a 90%+ reduction in
> effective computer speed.

Could you explain where this performance reduction comes from?  I agree
that forcing computation to be deterministic will slow it down, but I
didn't think it needed to be by that magnitude.

-Eric