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  1. MariaDB Server
  2. MDEV-17251

SHOW STATUS unnecessary calls calc_sum_of_all_status

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      SHOW GLOBAL STATUS and INFORMATION_SCHEMA.GLOBAL_STATUS always invoke calc_sum_of_all_status() to aggregate values of global status variables from session status variables into a temporary buffer.

      This is done even when no such aggregated variable will be returned to the user (e.g. because of LIKE 'uptime'. And calc_sum_of_all_status() can be rather expensive with many threads, see MDEV-15135, so it's a waste to call it and not use the result.

      The fix could be to call calc_sum_of_all_status() from show_status_array() when it stumbles upon a first variable that needs aggregation.

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              Assignee:
              serg Sergei Golubchik
              Reporter:
              serg Sergei Golubchik
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