Re: Robust Futexes status

[david singleton <dsingleton@mvista.com>]

On Oct 23, 2005, at 8:48 PM, Sven-Thorsten Dietrich wrote:

> On Sun, 2005-10-23 at 13:52 -0700, david singleton wrote:
> > 	Inaky Perez-Gonzalez   has a wonderful suite of performance, stress 
> > and
> > functionality tests for the fusyn pthreads mutex package.
>
> > 	The graphs are just to show relative performance for the different
> > flavor kernels.  The
> > kernel's perform quite closely regardless of the 'flavor' of kernel.
> > The kernels have quite a few
> > debugging options turned so I can look for any problems so performance
> > is not optimal.
>
> The Mutex ownership change seems to climb with waiting threads.
>
> Its hard to tell with the log-n X-axis scale, but does this possibly
> correlate to the deadlock-detect option?

It could be.  I have been running all the tests mainly as stress and
functionality tests.
> If Deadlock-detect is enabled we should be seeing a graph proportional
> to n-squared on a linear X axis.
>
> If deadlock detect is disabled, the wait time should plateau for very
> large N.

The original run script ran up to 7500 waiting threads.  I ran a version
that only went up to 400 threads.

When I get full performance data I'll post it.

David
> Sven
>
>
> > 	It appears the robust futex functionality is healthy in all flavors 
> > of
> > kernel.
> >
> > 	
> >
> > David
> --
> ***********************************
> Sven-Thorsten Dietrich
> Real-Time Software Architect
> MontaVista Software, Inc.
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>
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