[ILUG] 2.6 Kernel + Hyperthreading

[Eoin Ryan]

Hi Everyone,

We have a rack of Dell Poweredge 750's which we use as processing nodes
for scientific experiments.  The CPU's are P4s with HT.  Currently, the
2.6.8-smp kernel is running on the cluster, so /proc/cpuinfo sees each
machine as having 2 processors.

I've spent the last few days googling to find some answers to my
questions without much luck, so I was hoping someone on this list might
have had experience with this.

1) How well will *non-threaded* applications perform?  Will they only
get 1/2 the CPU power?
	- Most of the apps are not threaded, so might I be better off
	  not using the HT capabilities?

2) How much of the HT capabilities are tied to the Scheduler/Kernel and
how much is hardware based?
	- Would it be worth trying out the -mm & other development
	  kernels?

3) Are there any accepted benchmark test suites available that I could
use to run my own tests and compair the performance of different
kernels?

Thanks,
Eoin.