On Sat, 19 Mar 2011, Bruce Evans wrote:
On Fri, 18 Mar 2011, Kostik Belousov wrote:
We definitely do not support configurations with different models of
CPUs in SMP, this is what Simmetric is about. Different as in frequency
or stepping.
...
Now there is even more asymmetry
in core frequencies, with the hardware transiently slowing down or
stopping cores independently, at least for cores in different packages.
Also, with virtualization, the virtualizer cannot reasonably even provide
an invariant TSC that runs at the same rate on all cores. It should
provide an invariant TSC that claims to run at the same rate on all cores,
but then the cores cannot run at the same rate except on average,
since some of the cores will have to run the virtualizer some of the
time, and it is unreasonable to distribute the overhead for this evenly
except on average.
Bruce
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
To unsubscribe, send any mail to "[email protected]"
