Hyperthreading in 6.x ... still frowned upon?
noackjr at alumni.rice.edu
Thu May 4 21:54:28 UTC 2006
Marc G. Fournier wrote:
> In 4.x, it was a 'shut it off' sort of deal .. my new amd64 don't appear
> to have it enabled, but my older i386 server that I just upgraded to 6.x
> user pid %cpu %mem vsz rss tt state start time command
> root 14 104.0 0.0 0 8 ?? RL 11:38AM 0:55.02 [idle:
> root 11 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle:
> root 13 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle:
> root 12 98.0 0.0 0 8 ?? RL 11:38AM 0:54.54 [idle:
> Is it still something that I should disable, and, if so, how in 6.x?
According to the 6.0 i386 Release Notes, you should use the
machdep.hyperthreading_allowed sysctl to disable Hyper-Threading.
If you are concerned with security, you should disable it. If you are
more concerned with performance, you should test your workload
with/without Hyper-Threading and choose the configuration which performs
More information about the freebsd-stable