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About lockfree queues ...

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Hello,


I have wrote before this:

"I have come to an interresting subject about lockfree queues,
if you take a look at those lockfree queues, like in transactional 
memory, if the data have changed those lockfree queue retries and loop 
again, but this (lockfree) mechanism generates a lot of cache-coherence 
traffic, so i will not advice this lockfree mechanism, so how
can we do it ? you can take a look at the MCS queue Lock , i
think they are doing it like a waitfree linklist that doesn't spin and
that reduces a lot the cache-coherence traffic, other than that
if your memory manager is not optimal and uses a lockfree mechanism and 
generates a lot cache-coherence traffic, so you have to use a freelist 
to lower the cache coherence traffic."


But you have to know even that you are using spin waits inside lockfree 
algorithms that genrates a lot of cache-coherence traffic , you have
to know that you can avoid this problem and make your lockfree queue 
more efficient by adding an exponential backoff to you lockfree 
mechanism using a PAUSE asm instruction followed by a Sleep(0) to not 
freeze the computer and this way , like with the Spinlock, it will 
reduce the cache-coherence traffic and make your lockfree queue more 
efficient,.




Thank you,
Amine Moulay Ramdane.

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About lockfree queues ... aminer <aminer@toto.net> - 2013-09-24 19:16 -0700
  Re: About lockfree queues ... aminer <aminer@toto.net> - 2013-09-24 21:09 -0700
  Re: About lockfree queues ... aminer <aminer@toto.net> - 2013-09-24 21:34 -0700

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