Re: [AMD64-SMP] I can't get my cpus working at 100%

On Thu, Aug 24, 2006 at 08:09:35PM +0200, Laurent C wrote:
Hello all,

I can't get my athlon x2 processor working at 100% on cpu-intensive apps.
I've made some tests with "john --test" and "transcode", wich are both
multithreaded apps.

For example if I launch transcode it takes between 50% and 55% cpu (on top),
and if I launch
a second transcode session on another file, the total cpu used on top is
100%, without lower the speed
of the first transcode session.

The same behavior occurs with john. A single "john --test" give me some
speed results, and the same
command with a transcode or second "john --test" give me the same speed
results but now with 100%
cpu used.

I made a "portupgrade -auf" just after building and installing my SMP kernel
and World, to be sure all is up-to-date.

So it's seems it's not a "top" output problem, but a real underuse of the
computing power.

%uname -a
FreeBSD wks02.chez.oim 6.1-STABLE FreeBSD 6.1-STABLE #0: Thu Aug 17 18:47:31
CEST 2006 laurent@xxxxxxxxxxxxxx:/usr/obj/usr/src/sys/WKS02_SMP amd64

Does anyone could explain me what's happening with my system ?

How do you know the applications are running with two threads?
Presumably you need to specify the amount of parallelism.

Kris

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