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
>>
>>
>>
>>
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