Dual Core vs HyperThreading vs Dual CPU

Martin Cracauer cracauer at cons.org
Thu Jan 12 08:29:19 PST 2006


> > I have benchmarks comparing dual-core 939
> > socket systems against dual
> > 940 socket systems here:
> >
> http://cracauer-forum.cons.org/forum/crabench.html
> 
> Just a question about your benches, any reason
> you just don't ship files to /dev/null? That was
> always the standard in unix to get the disk out
> of it.

I am not sure what specific test you are referring to, but in general
I avoid using /dev/null as a sink like the plague.  Speed on /dev/null
varies drastically between OSes, and sometimes between kernel versions
(e.g. SMP and non-SMP kernel).  In combination with other load it
becomes unpredictable.  Any benchmark doing dd of=/dev/null is bogus
IMHO. 

My cstream utility has a build-in disgard option which avoids this
problem.

Martin
-- 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Martin Cracauer <cracauer at cons.org>   http://www.cons.org/cracauer/
FreeBSD - where you want to go, today.      http://www.freebsd.org/


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