MantisBT - Hall D Offline
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IDProjectCategoryView StatusDate SubmittedLast Update
0000443Hall D OfflineGeneralpublic2015-01-05 13:402015-01-05 13:41
Reporterdavidl 
Assigned Todavidl 
PrioritynormalSeverityminorReproducibilityalways
StatusresolvedResolutionwon't fix 
PlatformOSOS Version
Summary0000443: Mismatch of number of events passed to MergeObjLists Exception
DescriptionPaul M. and Mark D. both reported seeing this issue for runs 1518 and 2205 respectively. The symptom is an exception message such as the following. IT was reported for runs 1518, 2200, and 2205, though they are probably the tip of the iceberg.

Mon Dec 22 18:56:12 2014 # thr=139666653529856 # --- EVIO ---: Mismatch of number of events passed to MergeObjLists. Throwing exception.
Mon Dec 22 18:56:12 2014 # thr=139666653529856 # --- EVIO ---: Nevents1=1 Nevents2=2
JANA ERROR>>Exception thrown from ParseEVIOEvent!
JANA ERROR>>
JANA ERROR>>?JException: code = 0 text = Number of events in JEventSource_EVIO::MergeObjLists do not match!
JANA ERROR>>
JANA ERROR>>Stack trace:
JANA ERROR>>
JANA ERROR>> jana::JException::getStackTrace(bool, unsigned long)
JANA ERROR>> jana::JException::JException(std::string const&)
JANA ERROR>> JEventSource_EVIO::MergeObjLists(std::list<JEventSource_EVIO::ObjList*, std::allocator<JEventSource_EVIO::ObjList*> >&, std::list<JEventSource_EVIO::ObjList*,
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Issue History
Date ModifiedUsernameFieldChange
2015-01-05 13:40davidlNew Issue
2015-01-05 13:41davidlNote Added: 0000625
2015-01-05 13:41davidlStatusnew => resolved
2015-01-05 13:41davidlResolutionopen => won't fix
2015-01-05 13:41davidlAssigned To => davidl

Notes
(0000625)
davidl   
2015-01-05 13:41   
Below is a message sent to the halld-offline mailing list regarding this on Jan. 5, 2015:

Hi Offliners,

  I’ve received a couple of reports about errors containing lines similar to the ones below when processing
commissioning data. This problem seems to be hardware related. A single fADC125 module for the CDC
occasionally had a flaky bit 19 in the itrigger value it reported. This causes the code to treat it as a separate
event, thus the mismatch in “events" coming from this module compared to all others. As such, the error message
is actually valid and correct. This issue can be ameliorated by setting the configuration parameter EVIO:ENABLE_DISENTANGLING
to “0”. e.g.

hd_root -PEVIO:ENABLE_DISENTANGLING=0 …

This only works for files taken with CODA block level=1. For all useful commissioning data this was the case.

We can discuss how best to handle these types of errors since automatically suppressing them is not really
good. However, specifying the above often can be a bit annoying too. Suggestions are welcome.