To hyper-thread or not to hyper-thread

[Chris Adams]

Once upon a time, Greg Woods <woods at ucar.edu> said:
> One feature in particular that is not present twice is some of the
> caching. This is sort of why they named it "hyperthreading". If you can
> get multiple threads of the same process, sharing the same memory, to
> run simultaneously, there is a performance boost. But if you try to run
> two completely different processes simultaneously, there will actually
> be a performance LOSS because of all the cache misses this will cause.

I believe that the Linux kernel scheduler takes all of this into
account.  You are better off enabling HT (and letting the kernel worry
about taking advantage of it) than disabling it.

-- 
Chris Adams <cmadams at hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.