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Thread 'Running multiple work units on the same computer simultaneously'

Thread 'Running multiple work units on the same computer simultaneously'

Questions and Answers : Getting started : Running multiple work units on the same computer simultaneously
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old_user25557

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Message 5800 - Posted: 31 Oct 2004, 15:53:42 UTC

I\'m running CP on three machines. One of them, curiously, is working it\'s way through two work units simultaneously, and just as quickly as the other two machines. This machine is a bit (though not a lot) stronger than the other two - does CP automatically add extra concurrent work units to a machine if it can handle the load? Is there any way I can manually request additional concurrent work units for any of my machines?

Thx
Phil
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ProfileAndrew Hingston
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Message 5801 - Posted: 31 Oct 2004, 16:05:28 UTC
Last modified: 31 Oct 2004, 16:07:06 UTC

You've hidden details of your computers so we will have to guess the details :), but the machine running two models will be a Pentium with 'hyperthreading' (HT). That gives it the ability to run two programs at once. You can't do this on the other computers unless they have this feature (which will rule out older machines).

There is a setting in General Preferences that enables you to switch this feature on and off - <i>On multiprocessors, use at most ...</i>. Actually, if you tell BOINC to use only one it will run faster than if you use both, but overall you will do more work, and earn more credits, if you do run both.
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crandles
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Message 5802 - Posted: 31 Oct 2004, 16:08:00 UTC
Last modified: 31 Oct 2004, 16:10:14 UTC

I would assume you have a computer that is capable of hyperthreading. If enabled and if you left the default use no more than 2 CPUs, BOINC will download a model for each of the two virtual processors.

If your other computers have HT processors, you may want to ensure it is on in the BIOS and check that preference setting.

HTH

Oh Andrew has beaten me to the answer.
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Questions and Answers : Getting started : Running multiple work units on the same computer simultaneously

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