[ILUG] 2.6 Kernel + Hyperthreading

[Paul Jakma]

On Thu, 9 Sep 2004, Ronan Cunniffe wrote:

> Almost certainly switch it off.

Hmm, doesnt that depend?

> Intel's answer was to create *two* feeds into the mouth of the 
> pipe, to keep it fed with useful work.  From the outside, it looks 
> like two processors, but if you get at most a 30% speed advantage, 
> and only if the two threads aren't trying to do the same kind of 
> work.

But if you have different tasks and/or tasks that arent cache 
intensive (eg mostly IO), isnt it better on?

> I manage Xeon machines currently being used for Monte Carlo 
> simulations - a few short tests showed that HT on definitely wasn't 
> better, might be worse.

But isnt HT a win for server workloads?

> Ronan

regards,
-- 
Paul Jakma	paul at clubi.ie	paul at jakma.org	Key ID: 64A2FF6A
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