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 does: 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: cpu0] root 11 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle: cpu3] root 13 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle: cpu1] root 12 98.0 0.0 0 8 ?? RL 11:38AM 0:54.54 [idle: cpu2] Is it still something that I should disable, and, if so, how in 6.x? Thx ---- Marc G. Fournier Hub.Org Networking Services (http://www.hub.org) Email: scrappy@hub.org Yahoo!: yscrappy ICQ: 7615664
> > In 4.x, it was a 'shut it off' sort of deal .. my new amd64 don'tappear> to have it enabled, but my older i386 server that I just upgraded to6.x> does: > > > Is it still something that I should disable, and, if so, how in 6.x? >Can you disable it in the BIOS or do you dual boot this machine?
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 does: > > 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: cpu0] > root 11 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle: > cpu3] > root 13 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle: > cpu1] > root 12 98.0 0.0 0 8 ?? RL 11:38AM 0:54.54 [idle: > cpu2] > > Is it still something that I should disable, and, if so, how in 6.x?You should test it for the workloads you have, but most of the time, HT isn't especially helpful. AMD64 CPUs come in dual-core format rather than HT-enabled. If you've seen "HT" or "HTT" applied to an AMD system, it's likely an abbreviation for "HyperTransport" or "HyperTransport Technology". -- -Chuck
On Wed, May 03, 2006 at 11:42:18AM -0300, 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 > does:I am not sure I understood your problem correctly... Do you want to enable hyperthreading on amd64? But they have no such thing. Intel only. -- Spartak Radchenko SVR1-RIPE
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 > does: > > 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: > cpu0] > root 11 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle: > cpu3] > root 13 99.1 0.0 0 8 ?? RL 11:38AM 0:00.00 [idle: > cpu1] > root 12 98.0 0.0 0 8 ?? RL 11:38AM 0:54.54 [idle: > cpu2] > > 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 best. -Jonathan