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POHow fast can Lock() be or are proxy lists the issue?
 

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  1. POHow fast can Lock() be or are proxy lists the issue?
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    <p><strong>Specification of the problem:</strong></p> <p>I am running some complex tasks in python and to speed it up, I decided to use pythons multiprocessing library. It worked pretty well, but after some time I started to wonder, how much time are the Locks, I use, consuming and how much are the processes blocking each other.</p> <p><strong>The structure of processes is following:</strong></p> <p>One process that updates shared list between processes. Code of data update is something like this:</p> <pre><code>lock.acquire() list_rex[0] = pat.some_list list_rex[1] = pat.some_dictionary lock.release() </code></pre> <p>where list_rex and lock are defined by </p> <pre><code>list_rex = manager.list([[some_elements], {some_elements}]) lock = multi.Lock() </code></pre> <p>And then there are several processes, that once in a while updates their own memory space with these list.The code is as follows:</p> <pre><code>lock.acquire() some_list = list_rex[0] some_dict = list_rex[1] lock.release() </code></pre> <p>some_list and some_dict are somehow related so I can not allow processes to have information in some_list from different update than is in some_dict.</p> <p><strong>And my question is</strong>, how fast are the methods acquire() and release()? In my case they can be called within seconds and sometimes milliseconds. <strong>And/Or</strong> is there some way how to avoid using locks in my case?</p> <p>Thank you for your time.</p> <p><strong>EDIT:</strong> after considering your comment my question probably should be - how are proxy lists affecting my calculations? I use "some_list" and "some_dict" really a lot to be read from after the update.</p>
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    1. USJendas
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    1. COI don't have any reliable references, but my guess would be that using a proxy list could slow you down much more than the locks. See [this question](http://stackoverflow.com/q/13121790/1258041) of mine for an example.
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      1. USLev Levitsky
    2. COHmm I didn't think of that. I thought that the locks are the bottleneck. I will do some more research on that.
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      1. USJendas
    3. COYou can use [timeit](http://docs.python.org/2/library/timeit.html) module to measure execution time of a code.
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      1. USIgonato
 

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