Mike, "if this option is Disabled, is hyperthreading also Disabled?"
I would guess so. In the sense that OS will see only
one (bootstrap) processor, the no other hardware will
be activated. It will look like a single processor system.
Therefore OS will not dispatch any extra threads
in parallel, so no extra performance from HT.
However, if the system was originally configured as a
multiprocessor system, it will use a distinctive MP
kernel for OS. After other processors are being disabled,
the system will continue to use the same MP kernel, and
the task switching will carry some overhead.
So the performance
of MP kernel on single processor is lower than that for
the single-processor kernel. Therefore the comparisons
in the article are not valid, accurately speaking anyway.
If there are no specific BIOS switch to enable/disable
hyperthreading explicitly, this is really a matter of 1
versus 4, so your concerns are valid.
- Ali
P.S. "concerning electron migration" Honestly, I know very
little about electromigration, so it is unlikely that
I contributed anything to clarify the subject. But it
could be something else, so I thank you anyway ;-) ;-) ;-) |
