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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: 2381     Entry time: 04 Apr 2022     In reply to: 2380     Reply to this: 2476
Author: Konstantin Olchanski 
Topic: Suggestion 
Subject: Maximum ODB size 
> Anybody some idea what the maximum ODB size can be?

It turns out ODB size limit is hardwired on db_open_database() at 100 Mbytes.

I now committed an improved error message for this.

I confirm that "odbinit -s 100MB" works and creates ODB with 50 Mbyte data area and 50 
Mbyte key area.

> in the age of 64GB RAM being a standard, we should be able to grow bigger ...

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.

And creating extra large 1 GB ODB but using only a few megabytes will not waste any 
RAM, because the .ODB.SHM file is demand-paged and non-used parts of ODB will not be 
mapped into RAM. (It will waste disk space, file .ODB.SHM will be 1 GByte size).

However, 1 GByte (FPGA based) and 4-8 GByte (Raspberry Pi & co) machines are again
becoming popular and relevant for running MIDAS, and they have very slow "disk" 
subsystems, with NAND, SD and USB flash, so we should not go crazy here.

> odbinit -s 1024MB --cleanup

there is a bug in odbinit, if initial odbinit fails, ODB with default size is creates, 
and original rejected ODB size is written to .ODB_SIZE.TXT (an inconsistency).

bitbucket bug 328

> [ how do I resize ODB ??? ]

we need odbresize. bitbucket bug 329.

K.O.
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