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wjm

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Message 71431 - Posted: 8 Dec 2021, 16:11:17 UTC

There's some problem with this application, so I've suspended all instances of it. I'm running BIONC on an old HP Win10 Pro with an Intel Core I5. Generally nothing else is running on that computer other than a very little background syncing of data with other computers.

It seems to run N-Body properly with the CPU at 100%. But later when I look the utilization will be down near 0% and it stays there. If I suspend it and restart it, it will go back to 100% for long periods. No other BOINC project does this, and neither do other MilkyWay@Home applications.

The only solution seems to be to abort all instances of the N-Body.

FWIW.

wjm
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wjm

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Message 71432 - Posted: 8 Dec 2021, 16:18:27 UTC - in response to Message 71431.  

My apologies for somehow posting this thread twice. I cannot figure out how to delete the other version of the post, but if some moderator can, please do so.
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Profile Joseph Stateson
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Message 71433 - Posted: 8 Dec 2021, 17:32:19 UTC - in response to Message 71431.  
Last modified: 8 Dec 2021, 17:33:32 UTC

You might find this helpful
https://milkyway.cs.rpi.edu/milkyway/forum_thread.php?id=3333&postid=59553#59553

You are running two MW cpu apps. The N-body and the separation.
Looking at the n-body (only 1 was valid) the app is trying to use all 4 threads on a system that has only 4

The separation uses one thread.

Since you have all 4 threads available to boinc then you can run the following

Four separation tasks concurrently
One n-body.


==i am guessing===
If running one n-body after the 60 minute (maybe 120 ?) time slice is up then four of the separation start up.
after some time elapses one of the separation reports and a new tasks is downloaded.
after a time slice against one of the separation apps, boinc sees that there is only 1 CPU available so it cannot start the n-body.

I think you cannot run all those apps. Looks like the separation are working for you so select only seperation in project prefernces

HTH
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wjm

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Message 71434 - Posted: 8 Dec 2021, 17:50:32 UTC - in response to Message 71433.  
Last modified: 8 Dec 2021, 17:53:12 UTC

My system shows only the N-Body running when it locks up with 0% CPU. Once an N-Body terminates normally, the computer is happy to simultaneously run 4 Separation programs that are single CPU apps. BOINC seems to be smart enough to not run any other application while N-Body is running. At least in my limited experience.

Is there some way to tell MW to never send me the N-Body to run? Otherwise I seem only to be able to block MW altogether. (Never mind - I found the Preference for that)

Thanks.
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Message boards : Application Code Discussion : N-Body Simulation Problem

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