Message boards : Sixtrack Application : 10^5 in name, 10^6 in nature
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Profile Ray Murray
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Message 33827 - Posted: 13 Jan 2018, 12:51:21 UTC
Last modified: 13 Jan 2018, 13:03:05 UTC

I would normally expect 100,000 turn tasks to run for a little over an hour and million turn tasks to be 10 hours or more. However, much of this recent batch of work has seen tasks declared as 105 taking as long as a typical 106 job eg. LHC_2015_LHC_2015_234_BOINC_errors__15__s__62.31_60.32__4.9_5.0__5__55.5_1_sixvf_boinc51308_0 which ran for 13 hours. Has the naming convention been dropped or are these jobs looking more in depth to account for the longer runtime?
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Alessio Mereghetti
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Message 33831 - Posted: 13 Jan 2018, 15:44:46 UTC - in response to Message 33827.  

Hello Ray,
thanks for the acute question. No, those WUs are truly 10^5 turns. Contrary to many other cases with 10^5 turns, these tasks last longer, as they include the physics of beam-beam effects, i.e. non-linear forces between bunches at the interaction points (including parasitic encounters), which are CPU-expensive. The usual 10^5 turns jobs you are used to take into account only magnetic errors (which are treated at initialisation, but then they add 0 CPU extra time).
Hope it helps!
Cheers,
A.
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Profile Ray Murray
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Message 33835 - Posted: 13 Jan 2018, 18:52:43 UTC - in response to Message 33831.  

Thanks for that explanation, Alessio. I was just curious.
Sixtrack was one of my first Boinc projects so I try to catch as many as I can, when they're available.
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Message 33849 - Posted: 14 Jan 2018, 14:14:42 UTC - in response to Message 33835.  

Thanks a lot for your care, Ray, and for being generous with us! All my colleagues and I are very grateful!
Happy crunching!
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Message boards : Sixtrack Application : 10^5 in name, 10^6 in nature


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