CPU Time vs Credit


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Questions and Answers : Macintosh : CPU Time vs Credit

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Profile michaelmastro
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Message 877532 - Posted: 20 Mar 2009, 18:20:20 UTC

If I complete a task that takes 8,000 seconds, and a unit that takes 40,000 seconds, why do they get the same credit? I would think that consuming 5 times the cpu time should receive 5 times the credit. What's the story?

Thank you in advance.
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Message 877538 - Posted: 20 Mar 2009, 18:36:22 UTC

Such a simple question that requires a long, drawn out explanation, but I'll try to summarize for you to spare you the lengthy reading.


Credit is not granted for CPU seconds but for Floating Point Operations Per Second, which is largely different. For one CPU, it may be able to perform more FPOPs per unit, finishing the result in 8,000 seconds. Whereas with a different CPU it may be able to perform fewer FPOPs per unit, finishing the result in 40,000 seconds but essentially performing the same amount of calculations over a longer period of time.
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Profile michaelmastro
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Message 877544 - Posted: 20 Mar 2009, 18:45:56 UTC - in response to Message 877538.

Hmmmmm. That makes sense... sort of, except that the work in question was performed on the same machine. I have an Astropulse unit on my Vista machine at home that will take 140 hours. In the past, Astropulse work credit is basically the same as a unit that only takes hours.
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Profile michaelmastro
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Message 877546 - Posted: 20 Mar 2009, 18:51:50 UTC - in response to Message 877538.

I think I just figured out the discrepancy - the work unit in question ran on my old Mac G4 which is a bit slower than my 24" iMac (Dual 533 vs Dual 2.8)
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Profile michaelmastro
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Message 877547 - Posted: 20 Mar 2009, 18:52:36 UTC - in response to Message 877546.

No my question is why my BoincStats signature shows as a url, instead of the stats. Pardon my ignorance...
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Message 877549 - Posted: 20 Mar 2009, 18:54:20 UTC - in response to Message 877547.
Last modified: 20 Mar 2009, 18:56:12 UTC

No my question is why my BoincStats signature shows as a url, instead of the stats. Pardon my ignorance...


Add [img] [/img] tags to your sig.

[edit] Like this:


To see how I did that, press the quote button and you'll see what I did.
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Profile michaelmastro
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Message 877552 - Posted: 20 Mar 2009, 19:00:18 UTC - in response to Message 877549.

Ta Da!!! Thanks for the assistance...

Michael
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Message 877554 - Posted: 20 Mar 2009, 19:02:52 UTC - in response to Message 877552.

You're welcome. :)
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Questions and Answers : Macintosh : CPU Time vs Credit

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