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Entry  30 Mar 2016, Belina von Krosigk, Forum, mserver ERR message saying data area 100% full, though it is free 
    Reply  26 Feb 2024, Maia Henriksson-Ward, Forum, mserver ERR message saying data area 100% full, though it is free 
Message ID: 2718     Entry time: 26 Feb 2024     In reply to: 1173
Author: Maia Henriksson-Ward 
Topic: Forum 
Subject: mserver ERR message saying data area 100% full, though it is free 
> Hi,
> 
> I have just installed Midas and set-up the ODB for a SuperCDMS test-facility (on
> a SL6.7 machine). All works fine except that I receive the following error message:
> 
> [mserver,ERROR] [odb.c:944:db_validate_db,ERROR] Warning: database data area is
> 100% full
> 
> Which is puzzling for the following reason:
> 
> -> I have created the ODB with: odbedit -s 4194304
> -> Checking the size of the .ODB.SHM it says: 4.2M
> -> When I save the ODB as .xml and check the file's size it says: 1.1M
> -> When I start odbedit and check the memory usage issuing 'mem', it says: 
> ...
> Free Key area: 1982136 bytes out of 2097152 bytes
> ...
> Free Data area: 2020072 bytes out of 2097152 bytes
> Free: 1982136 (94.5%) keylist, 2020072 (96.3%) data
> 
> So it seems like nearly all memory is still free. As a test I created more
> instances of one of our front-ends and checked 'mem' again. As expected the free
> memory was decreasing. I did this ten times in fact, reaching
> 
> ...
> Free Key area: 1440976 bytes out of 2097152 bytes
> ...
> Free Data area: 1861264 bytes out of 2097152 bytes
> Free: 1440976 (68.7%) keylist, 1861264 (88.8%) data
> 
> So I could use another >20% of the database data area, which is according to the
> error message 100% (resp. >95%) full. Am I misunderstanding the error message?
> I'd appreciate any comments or ideas on that subject!
> 
> Thanks, Belina

This is an old post, but I encountered the same error message recently and was looking for a 
solution here. Here's how I solved it, for anyone else who finds this: 
The size of .ODB.SHM was bigger than the maximum ODB size (4.2M > 4194304 in Belina's case). For us, 
the very large odb size was in error and I suspect it happened because we forgot to shut down midas 
cleanly before shutting the computer down. Using odbedit to load a previously saved copy of the ODB 
did not help me to get .ODB.SHM back to a normal size. Following the instructions on the wiki for 
recovery from a corrupted odb, 
https://daq00.triumf.ca/MidasWiki/index.php/FAQ#How_to_recover_from_a_corrupted_ODB, (odbinit with --cleanup option) should 
work, but didn't for me. Unfortunately I didn't save the output to figure out why. My solution was to manually delete/move/hide 
the .ODB.SHM file, and an equally large file called .ODB.SHM.1701109528, then run odbedit again and reload that same saved copy of my ODB. 
Manually changing files used by mserver is risky - for anyone who has the same problem, I suggest trying odbinit --cleanup -s 
<yoursize> first.
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