[asterisk-dev] (Possibly) Unnecessary futex calls

[Philipp Kempgen]

Tilghman Lesher schrieb:
> On Friday 20 February 2009 08:50:01 Benny Amorsen wrote:
>> Sean Bright <sean.bright at gmail.com> writes:
>> > Benny Amorsen wrote:
>> >> there. However, what is pid 8947 doing?! It seems to be waking up
>> >> because of a futex at least 25 times a second.
>> >
>> > Perhaps a silly question, but...
>> >
>> > All of those PIDs (25451, 25452, and 8947) belong to an Asterisk process?
>>
>> Yes, they're actually thread ID's not process ID's. Not that there's
>> much difference in Linux, but I should still get it right.
> 
> In answer to your original question, this is probably the underlying
> implementation of a mutex.  In this case, it's a mutex with contention,
> relying on the kernel to provide contention resolution.

In layman's terms: It's not a bug in Asterisk then?

FWIW: I have seen the problem with the current 1.6.1 branch on a
2.6.26-1-686 kernel.


    Philipp Kempgen
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