[TriLUG] Hyperthreading and Xeons

[Scott R. Chilcote]

Hi Jeremy,

Jeremy Portzer wrote:
> Does this mean that I should treat it as a four-processor computer for
> the purposes of starting processes?  For example, I have a program that
> runs as many copies of itself as there are processors (but you have to
> tell it how many processors there are).  Should I let it run four copies
> or stick with two?

I use a hyperthreaded dual Xeon system for building source code.  I have 
found that running make with as many as eight jobs simultaneously [-j8] 
results in faster completion times than with fewer jobs.

> Any other consequences to hyperthreading I should know about?

I understand that while there is adequate HT support in the newer 2.4 
kernels, 2.6 is supposed to use it more efficiently.  I can't think of 
any relevant problems.

--
Scott C.