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Questions and Answers : Macintosh : Why do jobs pause every 30-40 seconds?

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richard schumacher
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Message 43557 - Posted 13 Dec 2011 13:44:41 UTC

    Four different hadcm3n_um_6.07_i686-apple-darwin jobs are running simultaneously. Every 30-40 seconds they each pause for 5-10 seconds, but not necessarily at the same moment. Activity Monitor shows no disk or network activity associated with these pauses. I've tried all the BOINC preferences on resource allocation and runtimes with no effect. What's going on?
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    Les Bayliss
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    Message 43558 - Posted 13 Dec 2011 14:16:50 UTC - in response to Message 43557.

      This is where the program does a "heat exchange" between the many cells that make up the atmosphere.

      See this page for more info on how the atmosphere is divided up.



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      richard schumacher
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      Message 43559 - Posted 13 Dec 2011 14:19:06 UTC - in response to Message 43558.

        Thanks!
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        Jimmy Gondek
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        Message 43610 - Posted 26 Dec 2011 22:25:45 UTC

          Last modified: 26 Dec 2011 22:27:13 UTC

          Hi Richard,

          I noticed the same behavior in Activity Monitor on my iMac when I began running this project, too. It appears to me to be what happens everytime the CPDN/BOINC software performs a "checkpoint" of each of the Work Units. If you go into the Advanced menu in BOINC Manger and select "Event Log..." you'll be able to view what is going on in real time.

          :)

          Les Bayliss
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          Message 43612 - Posted 27 Dec 2011 2:52:56 UTC - in response to Message 43610.

            As I said before, it's when the program pauses the calculations of what's happening in each "cell", to exchange data between each adjacent cell, ready for the next iteration of calculations. Otherwise the model would just be a large number of totally isolated little worlds a few miles across.
            One of these exchanges also occurs just as the program does a checkpoint.


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            Questions and Answers : Macintosh : Why do jobs pause every 30-40 seconds?




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