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Message boards : Technical Support : Computation Error (17 CPUs)

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Aurum
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Joined: 1 Oct 17
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Message 21535 - Posted: 9 Oct 2017, 13:28:34 UTC

I have C@H running on several rigs with Xeon E5 CPUs (24-28 cores). Some get only 6-CPU WUs, others 8_CPU and some get 17-CPU. The small ones seem to run without any problems but the big ones may run the first but then dump all the rest as Computation Errors. Could it have anything to do with trying to use a prime number of cores??? I've heard tales that was a problem on another project.
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Jonathan
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Message 21537 - Posted: 10 Oct 2017, 0:14:58 UTC - in response to Message 21535.

You may need to limit them to 8 cpus per workunit. This was discussed in another forum thread. Following is a copied app_config from the other forum. You would save this as 'app_config.xml' in the Cosmology directory of Boinc. You can change the avg_ncpus to whatever you want that is less than eight to get as much utilization as you desire.

<app_config>
<app_version>
<app_name>camb_boinc2docker</app_name>
<plan_class>vbox64_mt</plan_class>
<avg_ncpus>8</avg_ncpus>
</app_version>
</app_config>

Message boards : Technical Support : Computation Error (17 CPUs)