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Entry  31 Mar 2022, Stefan Ritt, Suggestion, Maximum ODB size 
    Reply  04 Apr 2022, Konstantin Olchanski, Suggestion, Maximum ODB size 
       Reply  27 Apr 2023, Marius Koeppel, Suggestion, Maximum ODB size 
          Reply  27 Apr 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
             Reply  27 Apr 2023, Marius Koeppel, Suggestion, Maximum ODB size 
                Reply  27 Apr 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                Reply  27 Apr 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                   Reply  28 Apr 2023, Marius Koeppel, Suggestion, Maximum ODB size create_time.pdffails.pdftest_odb.py
                      Reply  28 Apr 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                         Reply  28 Apr 2023, Marius Koeppel, Suggestion, Maximum ODB size 
                         Reply  28 Apr 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
             Reply  27 Apr 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                Reply  28 Apr 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                   Reply  09 Jun 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                      Reply  12 Jun 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                         Reply  12 Jun 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                            Reply  13 Jun 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                               Reply  13 Jun 2023, Marius Koeppel, Suggestion, Maximum ODB size 
                                  Reply  13 Jun 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                               Reply  13 Jun 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                                  Reply  13 Jun 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                                     Reply  13 Jun 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                                        Reply  13 Jun 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                                           Reply  15 Jun 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
                                              Reply  28 Jul 2023, Stefan Ritt, Suggestion, Maximum ODB size 
                                                 Reply  09 Aug 2023, Konstantin Olchanski, Suggestion, Maximum ODB size 
Message ID: 2538     Entry time: 13 Jun 2023     In reply to: 2537     Reply to this: 2539
Author: Konstantin Olchanski 
Topic: Suggestion 
Subject: Maximum ODB size 
> 
> > small problem. build an experiment, start taking data, observe how ODB is never saved to disk because the "last client" never stops. as bonus, crash 
> > the computer, observe how all changes to ODB are now lost. if mlogger is configured to save odb.json at the end of run, and to write ODB dumps at 
> > begin and end of every data file, you can recover some of the lost 
> 
> The new behavior is not much worse than before. Assume 10 programs running happily for days, computer crashes, all ODB changes lost. 
> So indeed a periodic flush without holding the lock might be best. Use a semaphore to prevent all programs flushing at the same time, or put
> the flush only in the logger after an end of run.

are you sure? when/how often does "last midas program finishes" happen? it does not happen on a system crash, not on power loss, not on "shutdown -r now" 
(I am pretty sure). In the experiments you run, how often do you shut down all programs (and check that you did not forget one somehow)?

sanity check. dragon experiment, very active, .ODB.SHM timestamp is 1 second old. not-very-active agmini, today is June 13th, timestamp of .ODB.SHM is June 
2nd. inactive TACTIC, timestamp of .ODB.SHM is May 16th.

so yes, not great, but in the new scheme, ODB.SHM timestamps would probably be from 2021 or 2020.

my vote is to undo this change, it is dangerous because it causes odb to be saved to ODB.SHM never.

K.O.
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