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  1. Moodle
  2. MDL-62972

Backup including logs of external database uses a lot of DB connections

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Details

    • Bug
    • Status: Reopened
    • Minor
    • Resolution: Unresolved
    • 3.3.7, 3.4.4, 3.5.1, 3.11, 4.0
    • None
    • Backup, Database SQL/XMLDB, Logging
    • MOODLE_311_STABLE, MOODLE_33_STABLE, MOODLE_34_STABLE, MOODLE_35_STABLE, MOODLE_400_STABLE
    • MDL-62972_311
    • MDL-62972_master
    • Moderate
    • Hide

      Requirements:

      1. testing this issue requires a developer (DB creation, MySQL CLI...)

      Setup external database

      1. Create a database other than your Moodle database.
      2. Create a table in the above database identical to the logstore_standard in your Moodle database.

      Configuration of external database

      1. Go to Site administration ► Plugins ► Logging ► Manage log stores
      2. Enable External database log
      3. Go to settings for the external logstore
      4. Enter your external database and table details and save
      5. Click on "Test connection" and make sure you can successfully connect to the database table.

      Step-By-Step

      1. Run a manual backup of a course (GUI) with a good number of activities. Ensure to include course logs in backup
      2. In parallel monitor the mysql connections over the CLI e.g. 

        while [ true ]; do mysql -u MYSQLUSERNAME -p'MYSQLUSERPASSWORD' --execute='SHOW FULL processlist;'; sleep 1; done;

      Show
      Requirements: testing this issue requires a developer (DB creation, MySQL CLI...) Setup external database Create a database other than your Moodle database. Create a table in the above database identical to the logstore_standard in your Moodle database. Configuration of external database Go to Site administration ► Plugins ► Logging ► Manage log stores Enable External database log Go to settings for the external logstore Enter your external database and table details and save Click on "Test connection" and make sure you can successfully connect to the database table. Step-By-Step Run a manual backup of a course (GUI) with a good number of activities. Ensure to include course logs in backup In parallel monitor the mysql connections over the CLI e.g. while [ true ]; do mysql -u MYSQLUSERNAME -p 'MYSQLUSERPASSWORD' --execute= 'SHOW FULL processlist;' ; sleep 1 ; done;

    Description

      Mysql connections to external logstore are not reused/cached, so the amount of mysql connections is increasing.
      This can best be seen during automated course backup. Every database reading creates a new database connection. This connections are terminated when backup process is finished.

      Probably solution: Use a global variable $DBEXT like $DB, where the external mysql connection is cached.

       

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        Issue Links

          Testing discovered

          Bug - A problem which impairs or prevents Moodle from functioning correctly. MDL-72344 Restore including logs of external database uses a lot of DB connections

          • Minor - Minor loss of function where workaround is possible
          • Open

          Activity

            People

              Unassigned Unassigned
              voegi Sascha Vogel
              Ilya Tregubov Ilya Tregubov
              Adrian Greeve, David Woloszyn, Huong Nguyen, Jake Dallimore, Meirza, Michael Hawkins, Raquel Ortega, Safat Shahin, Stevani Andolo, David Woloszyn, Huong Nguyen, Jake Dallimore, Meirza, Michael Hawkins, Raquel Ortega, Safat Shahin, Stevani Andolo, David Woloszyn, Huong Nguyen, Jake Dallimore, Meirza, Michael Hawkins, Raquel Ortega, Safat Shahin, Stevani Andolo
              Votes:
              1 Vote for this issue
              Watchers:
              11 Start watching this issue

              Dates

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                Updated:

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