Subject Re: Excellent Intel resource for hyperthreading load imbalances
Author Adam
--- In, "Nigel Weeks" <nweeks@e...>
> Just in case people ask why their Hyperthreading server slows down with
> SuperServer, here's an excellent article from Intel explaining why the
> slow-down occurs.

They must have some pretty cluey people working there.

Load imbalance possible:
nLogicalProcessors - nActiveThreads > 1

Or in English.

It is possible to get suboptimal performance if you have more threads
than logical processors, but impossible if you have more logical
processors than things to do. well duh.

"The simplest way to avoid load imbalance is to make certain the
number of active threads in the system is always greater than or equal
to the number of logical processors in the system."

hmmmm, So create threads you don't actually need.

There is however some sample code to tie a thread to a single logical
processor, which may prove useful (Like CPUAffinity on a HT level)