Hyperthreading performance oddities

[belcampo <belcampo@zonnet.nl>]

Hi all,

I would like to be personally CC'ed the answers/comments posted to the 
list in response to my posting.

I have following CPU
vendor_id       : GenuineIntel
cpu family      : 15
model           : 4
model name      : Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping        : 1
cpu MHz         : 3000.000
cache size      : 1024 KB

on 2.6.17 everything works as I expect. My Mandriva distribution 
standard has a 2.6.22.9 kernel which performed bad, numbers follow, 
installed a fresh 2.6.24.2 kernel also performed bad, so I installed 
2.6.17 and everything works OK.
I have some benchmarks from mplayer:
Kernel 2.6.22.9 smp hyperthreading
BENCHMARKs: VC: 334.042s VO:   0.053s A:   0.000s Sys:   4.049s =  338.143s
Kernel 2.6.22.9 nonsmp/hyperthreading
BENCHMARKs: VC: 262.008s VO:   0.031s A:   0.000s Sys:   3.528s =  265.567s
with 2.6.17 kernel smp/hyperthreading pentium-pro as CPU
BENCHMARKs: VC: 245.175s VO:   0.050s A:   0.000s Sys:   2.479s =  247.704s
with 2.6.17 kernel smp/hyperthreading pentium4 optimized kernel
BENCHMARKs: VC: 227.992s VO:   0.051s A:   0.000s Sys:   2.551s =  230.594s

The 2.6.24.2 kernel had results as the 2.6.22.9 version

Regards Henk Schoneveld