Subject: Re: PTHREAD_CONCURRENCY and large SMP (8 CPUs)
To: NetBSD current <current-users@netbsd.org>
From: Pavel Cahyna <pcah8322@artax.karlin.mff.cuni.cz>
List: current-users
Date: 12/01/2005 17:49:32
On Thu, Dec 01, 2005 at 08:38:49AM -0800, Chuck Silvers wrote:
> On Thu, Dec 01, 2005 at 03:48:57PM +0100, Nicolas Joly wrote:
> > Hi,
> > 
> > While playing with a 8 CPUs amd64 machine (4x dual-core 865 Opterons),
> > i noticed that a simple threaded program (source attached) does not
> > work with PTHREAD_CONCURRENCY >= 6. I already tested this small
> > program on NetBSD/i386 and NetBSD/amd64, but never with 8 CPUs.
> > 
> > Is there anything i can tweak to make it work ?
> 
> the PTHREAD_CONCURRENCY stuff was never finished.  there is still work
> to be done in both the kernel and libpthread to make it functional,
> even for only 2 CPUs.  it's really easy to trigger that library assertion,
> and some people have triggered kernel assertions as well.

"Wow".

Would it be possible to disable this "feature" in the kernel until it is
fixed?

Pavel Cahyna