HTT and SMP question
Rumen Telbizov
altares at e-card.bg
Tue Apr 20 01:52:07 PDT 2004
> > Would you please point out some cases when HTT with machdep.hlt_logical_cpus=0
> > causes worse performance than machdep.hlt_logical_cpus=1?
> > I am using an HTT Xeon since recently and in my tests it showed that
> > machdep.hlt_logical_cpus=0 is better!
> > A simple ubench (spawning 2 processes) gives better results in 0 mode!
>
> My parallel package builds are slower on build machines with HTT.
> It's not a magic bullet.
>
> Kris
Hmm ... interesting. My simple/stupid synthetic tests
showed just the opposite. Anyway. Unfortunatelly I didn't
try to buildworld/kernel with -j2 (say). Shame on me!
Would you point to a case where machdep.hlt_logical_cpus=0 does
show better performance results? httpd ?
Is it not that exactly _parallel processing_ should be faster with HTT
than whithout ?
Thank you for your reply.
Rumen Telbizov
More information about the freebsd-stable
mailing list