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More about waitfree and lockfree...

From aminer <aminer@toto.net>
Newsgroups comp.programming.threads, comp.programming
Subject More about waitfree and lockfree...
Date 2014-04-22 20:20 -0700
Organization albasani.net
Message-ID <lj70vt$3c3$1@news.albasani.net> (permalink)

Cross-posted to 2 groups.

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Hello,


Question:

Amine , we are kind of lost, what is this waitfree
concurrent FIFO queue , and lockfree concurrent FIFO queue ?


Answer:

We have to be smart and understand that waitfree and lockfree
algorithms maximize the parallelism, but the lockfree
suffers from starvation and it's less efficient than
other algorithms whith a scenario of high contention and the lockfree
algorithm can not be used in realtime systems when you need
the process to complete any operation in a finite number of steps of 
finite time, the lockfree algorithm can not do that, and what about
waitfree ? as i have said the waitfree algorithm do maximize the 
parallelism and it is also starvation-free and it finishes
an operatoin such us the push() and a pop() of a concurrent FIFO queue
in a finite number of steps , and the waitfree is efficient in a 
scenario with high contention , so i have presented to you a
concurrent FIFO queue that is waitfree, but the number of threads
has to be fixed to calculate the number of steps that the push()
and pop() takes in a realtime time system.


I have also presented to you a faster concurrent FIFO queue
that is not waitfree but as i said before it has more parallelism than 
the two lock algorithm and the items will be pushed and popped in
a FIFO order and it scales well even if the number of threads are 
greater than the number of cores.

You can download all those concurrent FIFO queues from my website:

http://pages.videotron.com/aminer/




Thank you,
Amine Moulay Ramdane.


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More about waitfree and lockfree... aminer <aminer@toto.net> - 2014-04-22 20:20 -0700

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