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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: 2477     Entry time: 27 Apr 2023     In reply to: 2476     Reply to this: 2480   2483
Author: Konstantin Olchanski 
Topic: Suggestion 
Subject: Maximum ODB size 
> > I agree, I think we can safely bump the limit from 100 Mbytes to 1 Gbyte, maybe 1.5 or 
> > 1.99 Gbytes. Above that we run into 32-bit/31-bit cleanliness problems.
>
> We just went in and changed: int odb_size_limit = INT_MAX;//100*1000*1000; in odb.cxx.
>

This is change is wrong. As I wrote, ODB is not 64-bit clean and it is not 32-bit clean. We think is is 31-bit clean, so maximum size would be slightly less than 2 Gbytes.

> And we could create ODBs with 1GB and 1.5 GB.

Congratulations. created != "it works". for proper test, you should fill it with 1.5 GB of stuff, save to json file, reload from json file, save to a different json file and compare that they have same contents (minus timestamps).

We could spend a lot of time making odb 32-bit clean and give you 4GB-max ODB, but would it be useful? For large ODB, "save to .json" already takes a long time ("save to .xml" is slower, "save to .odb" ditto, also buggy). We already have complaints that runs take forever to start because mlogger 
takes a long time to write the ODB save file.

P.S. 64-bit clean ODB will be binary incompatible, all internal pointers are 32-bit right now.

K.O.
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