Re: Robust Futexes status

From: david singleton
Date: Mon Oct 24 2005 - 12:02:29 EST



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




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