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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: 2525     Entry time: 09 Jun 2023     In reply to: 2488     Reply to this: 2527
Author: Konstantin Olchanski 
Topic: Suggestion 
Subject: Maximum ODB size 
> > 1) The ODB shared memory is dumped into a binary file (".ODB.SHM") after the last client finished ...

correction: ODB shared memory is saved to .ODB.SHM each time a client stops, this is db_close_database().

I have just run into a problem with this in the DRAGON experiment. At begin and end of run they run
a script that does a large number of "odbedit" calls to read stuff from ODB and it was taking a very long time.
Each odbedit invocation was taking about 1 second, starting odbedit is quick, stopping odbedit takes about 1 second.

It turns out each invocation of odbedit saves .ODB.SHM, ODB was 100 Mbytes size, home disk is an HDD (~100-200 Mbytes/sec writing speed), so yes, about 1 second to 
stop odbedit.

Solution was to reduce ODB size from 100 Mbytes to 10 Mbytes, odbedit now run quickly, begin and end of run scripts run quickly. problem solved.

K.O.

P.S. no, I am not the dragon experiment, no, I did not write those scripts, no, I will not rewrite them, persons who wrote them are long gone, no, the persons running 
dragon today will not be rewriting them.
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