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  1. Moodle
  2. MDL-75907

The "\core\task\stats_cron_task" scheduled task gets stuck in large sites

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    Description

      Recently, scheduled task \core\task\stats_cron_task was found running in a transaction with the following SQL statment not completing in a reasonable time:

      INSERT INTO mdl_temp_stats_daily (stattype, timeend, courseid, roleid, stat1, stat2) SELECT 'activity', 1664460000 AS timeend, courseid, roleid, SUM(statsreads), SUM(statswrites) FROM (
      SELECT pl.courseid, pl.roleid, sud.statsreads, sud.statswrites FROM mdl_temp_stats_user_daily sud, ( SELECT DISTINCT te.userid, te.roleid, te.courseid FROM mdl_temp_enroled te WHERE te.roleid <> 19 AND te.userid <> 1 ) pl WHERE sud.userid = pl.userid AND sud.courseid = pl.courseid AND sud.timeend = 1664460000 AND sud.stattype='activity' ) inline_view GROUP BY courseid, roleid HAVING SUM(statsreads) > 0 OR SUM(statswrites) > 0;

      The transaction was held open for 4 days and this caused severe issues related to database performance.

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        1. MDL-75907_testing.png
          MDL-75907_testing.png
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        2. MDL-75907_v311.png
          MDL-75907_v311.png
          37 kB
        3. MDL-75907_v400.png
          MDL-75907_v400.png
          38 kB

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          People

            mikhailgolenkov Misha Golenkov
            mikhailgolenkov Misha Golenkov
            Dmitrii Metelkin Dmitrii Metelkin
            Victor Déniz Falcón Victor Déniz Falcón
            Angelia Dela Cruz Angelia Dela Cruz
            Matteo Scaramuccia, 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
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            Dates

              Created:
              Updated:
              Resolved:
              14/Nov/22

              Time Tracking

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                Logged:
                Time Spent - 35 minutes
                35m