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Crystal Pellet
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Message 2362 - Posted: 12 Mar 2016, 8:49:08 UTC

Shortly after a successful suspend/resume operation of a job, I very often see a WARNING message like

Begin processing the 11th record. Run 1, Event 2463011, LumiSection 29557 at 12-Mar-2016 09:14:23.145 CET
Begin processing the 12th record. Run 1, Event 2463012, LumiSection 29557 at 12-Mar-2016 09:32:35.407 CET
Begin processing the 13th record. Run 1, Event 2463013, LumiSection 29557 at 12-Mar-2016 09:32:35.724 CET
G4Fragment::CalculateExcitationEnergy(): WARNING
Fragment: A = 26, Z = 12, U = -2.152e-01 MeV IsStable= 1
P = (-7.712e+01,5.522e+01,6.635e+01) MeV E = 2.420e+04 MeV


Begin processing the 14th record. Run 1, Event 2463014, LumiSection 29557 at 12-Mar-2016 09:32:37.722 CET


Does this have any negative influence on the processed data?
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Message 2363 - Posted: 12 Mar 2016, 9:38:44 UTC - in response to Message 2362.  

As far as I know, no. That looks like a normal warning that a calculation has gone astray -- remember that most of the code has been written by grad students with little or no formal computer-science training... :-) ...and of course that floating-point calculations are often not exact. If we do establish a correlation with suspension that would be a little more worrying, but in any event the effect is going to be buried in the statistics (unless it's appearing as a SUSY particle!).
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Crystal Pellet
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Message 2366 - Posted: 12 Mar 2016, 10:44:49 UTC

Thanks Ivan,

I think that correlation is just my imagination.
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Message boards : Number crunching : Reliability of processed data


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