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Sebastian M. Bobrecki
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Message 39114 - Posted: 11 Dec 2014 | 8:24:21 UTC

I got this error:

Fatal error:
64 OpenMP threads were requested. Since the non-bonded force buffer reduction is prohibitively slow with more than 32 threads, we do not allow this. Use 32 or less OpenMP threads.
In that case, the maximum number of threads should be limited either in the application or the server side.

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Message 39117 - Posted: 11 Dec 2014 | 12:17:19 UTC - in response to Message 39114.

I got this error:
Fatal error:
64 OpenMP threads were requested. Since the non-bonded force buffer reduction is prohibitively slow with more than 32 threads, we do not allow this. Use 32 or less OpenMP threads.
In that case, the maximum number of threads should be limited either in the application or the server side.


To make this work on your machine I think you could limit the number of cpu's to 50% on that machine, get work, set it no new work, and then reset the cpu's back to 100%. This should force the cpu units to ONLY use the cpu's it saw when the units were downloaded, yet let you run other tasks on the other cores. It will be a pain to remember the steps every time you need more work, but after a few times it could become routine.

Setting the limit WITHIN the app though would be a MUCH better option, but that is the projects job and nothing a cruncher can do about it.

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Message 39118 - Posted: 11 Dec 2014 | 13:39:34 UTC - in response to Message 39117.

To make this work on your machine I think you could limit the number of cpu's to 50% on that machine, get work, set it no new work, and then reset the cpu's back to 100%.
Yes, I already figured it out.

This should force the cpu units to ONLY use the cpu's it saw when the units were downloaded, yet let you run other tasks on the other cores. It will be a pain to remember the steps every time you need more work, but after a few times it could become routine.
In my case, it didn't work that way. I mean, when I set cpu number back to 100%, other tasks didn't start.

Setting the limit WITHIN the app though would be a MUCH better option, but that is the projects job and nothing a cruncher can do about it.
I think that setting this in application, or perhaps somehow in project server configuration is the only sensible solution.

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Message 39124 - Posted: 11 Dec 2014 | 16:04:24 UTC - in response to Message 39114.

Limited to 32 now.

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Message 39137 - Posted: 12 Dec 2014 | 13:04:42 UTC - in response to Message 39124.
Last modified: 12 Dec 2014 | 13:05:32 UTC

Limited to 32 now.


Does this affect what we are talking about here:
"Increasing the maximum number of coprocessor devices to 64."

That is one of the changes in the latest version of Boinc that was just released for testing.
http://boinc.berkeley.edu/dev/forum_thread.php?id=8649

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Message 39138 - Posted: 12 Dec 2014 | 13:19:09 UTC - in response to Message 39137.

Limited to 32 now.


Does this affect what we are talking about here:
"Increasing the maximum number of coprocessor devices to 64."

That is one of the changes in the latest version of Boinc that was just released for testing.
http://boinc.berkeley.edu/dev/forum_thread.php?id=8649

No, it is about specific feature of the GROMACS application which is used by GPUGRID for this tasks.

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Message 39144 - Posted: 13 Dec 2014 | 12:45:16 UTC - in response to Message 39138.

Limited to 32 now.


Does this affect what we are talking about here:
"Increasing the maximum number of coprocessor devices to 64."

That is one of the changes in the latest version of Boinc that was just released for testing.
http://boinc.berkeley.edu/dev/forum_thread.php?id=8649


No, it is about specific feature of the GROMACS application which is used by GPUGRID for this tasks.


Ahhh, thanks for adjusting it then!

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Message boards : Multicore CPUs : Error with more than 32 threads

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