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Message ID: 2378     Entry time: 30 Mar 2022
Author: Konstantin Olchanski 
Topic: Bug Fix 
Subject: erroneous removal of odb clients, fixed 
made on 2022-02-21 fixed a serious bug in ODB.

a multithread race condition against an incorrectly updated shared variable caused removal of 
random clients from ODB with error message:

My client index %d in ODB is invalid: out of range 0..%d. Maybe this client was removed by a 
timeout, see midas.log. Cannot continue, aborting...

the race is between db_open_database() in one program (executed when any midas program starts) and 
db_get_my_client_locked() in all running midas programs.

as long as no midas programs are started (db_open_database() is not executed), this bug does not 

if i.e. odbedit is executed very often, i.e. from a script, probability of hitting this bug becomes 
quite high.

fixed now.

ELOG V3.1.4-2e1708b5