Is it possible to make -lpthread program to use 100% CPU?
Alexandre Sunny Kovalenko
Alex.Kovalenko at verizon.net
Sat May 1 17:42:40 PDT 2004
On Sat, 1 May 2004 14:49:47 -0400 (EDT)
Daniel Eischen <eischen at vigrid.com> wrote:
> On Sat, 1 May 2004, Alexandre Sunny Kovalenko wrote:
>
> > On Thu, 29 Apr 2004 17:16:21 +0200
> > Ivan Voras <ivoras at fer.hr> wrote:
> >
> > > Alexandre Sunny Kovalenko wrote:
> > >
> > > > Alternatively, if there is a need to test a patch or time a program
> > > > in this environment, it could easily be accomplished -- it is a non-
> > > > production box.
> > >
> > > Could you turn off Hyperthreading and report any changes?
> > >
> > >
> > > _______________________________________________
> > > freebsd-current at freebsd.org mailing list
> > > http://lists.freebsd.org/mailman/listinfo/freebsd-current
> > > To unsubscribe, send any mail to "freebsd-current-unsubscribe at freebsd.org"
> >
> > I have updated my system to the latest CTM mailing on Friday (4/30) morning (EST).
> > This includes version 1.176 of kern_thread.c.
> >
> > I have turned off hyperthreading and got result, which muddles me rather -- try
> > as I might, with -lpthread I could not get past 50% CPU utilization (as reported
> > by 'top') and number of computations per second matching that (number is very
> > close to that for running single-threaded). Top report with thread view enabled
> > shows that both KSE are bound to CPU 0 (if I am interpreting C column properly).
>
> Are you using system or process scope threads?
>
> --
> Dan Eischen
>
> _______________________________________________
> freebsd-current at freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-current
> To unsubscribe, send any mail to "freebsd-current-unsubscribe at freebsd.org"
Sorry, should have mentioned that too. For -lthr PTHREAD_SCOPE_PROCESS is only
available option. For -lpthread I have tried both, and results do not differ
much, which is what I expect on the machine that runs nothing else (unless
I do not understand PTHREAD_SCOPE_ option).
--
Alexandre "Sunny" Kovalenko.
More information about the freebsd-current
mailing list