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Entry  17 Nov 2020, Stefan Ritt, Info, Equipment "common" settings in ODB 
    Reply  20 Nov 2020, Pierre-Andre Amaudruz, Info, Equipment "common" settings in ODB 
    Reply  27 Nov 2020, Konstantin Olchanski, Info, Equipment "common" settings in ODB 
       Reply  27 Nov 2020, Stefan Ritt, Info, Equipment "common" settings in ODB 
          Reply  27 Nov 2020, Konstantin Olchanski, Info, Equipment "common" settings in ODB 
             Reply  30 Nov 2020, Stefan Ritt, Info, Equipment "common" settings in ODB 
                Reply  30 Nov 2020, Stefan Ritt, Info, Equipment "common" settings in ODB 
                   Reply  30 Nov 2020, Konstantin Olchanski, Info, Equipment "common" settings in ODB 
Message ID: 2014     Entry time: 17 Nov 2020     Reply to this: 2019   2032
Author: Stefan Ritt 
Topic: Info 
Subject: Equipment "common" settings in ODB 
Today I addressed a topic which bugged me since long time. The ODB contains 
settings under /Equipment/<name>/Common which are a "mirror" of the equipment[] 
setting in a frontend (using the mfe.cxx framework). If the "Common" entry in 
the ODB is not present (fresh experiment), the equipment[] settings from the 
frontend are copied to the ODB. But if it exists, it takes precedence over the 
equipment[] entries, which is wrong in my opinion. Like if you change some 
settings in equipment[] (like the logging period of the history), then recompile 
and restart the frontend, the old values in the ODB are kept and your 
modification in the frontend code has no effect.

Starting on commit c3017c6c on Nov. 17th 2020 I reversed the precedence: Now, on 
each start of the frontend program, the values from equipment[] are written to 
the ODB. They are still "live". If one changes them when the frontend is 
running, that change takes effect immediately. But on the next restart of the 
frontend, the old values from equipment[] is put back there.

I fell too many times into this trap, and I hope the modification helps 
everybody. If there are however experiments which rely on the fact that the 
common settings in the ODB are NOT overwritten by the frontend, please let me 
know and I can put a flag "EQUIPMENT_FE_PRECEDENCE = FALSE" somewhere to restore 
the old behaviour.

Stefan
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