Is it possible to make -lpthread program to use 100% CPU?

[Daniel Eischen]

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?
> > 
> > 
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> 
> 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