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  1. MariaDB Server
  2. MDEV-6934

os_event_wait_time_low(): wait time calculation is messed up

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      http://bugs.mysql.com/bug.php?id=72520

      In os_event_wait_time_low() the logic to calculate abs_time
      for wait is broken. The bug has been present at least since
      5.5. It gets acutely sensitized when sub-second wait intervals
      are passed. It is particularly relevant to us because the
      page_cleaner thread will mostly request sub-second wait
      intervals. This can potentially lead to a near tight loop
      behaviour of page_cleaner with much less sleep then what we'd
      actually expect.

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              jplindst Jan Lindström added a comment -

              revno: 4454
              committer: Jan Lindström <jplindst@mariadb.org>
              branch nick: 10.0-innodb
              timestamp: Fri 2014-10-24 17:11:09 +0300
              message:
              MDEV-6934: os_event_wait_time_low(): wait time calculation is messed up

              Merged Facebook commit bdab302a7e3c37da21a1bffe1550cdbe6c906695
              by Inaam Rana from https://github.com/facebook/mysql-5.6.

              In os_event_wait_time_low() the logic to calculate abs_time
              for wait is broken. The bug has been present at least since
              5.5. It gets acutely sensitized when sub-second wait intervals
              are passed. It is particularly relevant to us because the
              page_cleaner thread will mostly request sub-second wait
              intervals. This can potentially lead to a near tight loop
              behaviour of page_cleaner with much less sleep then what we'd
              actually expect.

              Show
              jplindst Jan Lindström added a comment - revno: 4454 committer: Jan Lindström <jplindst@mariadb.org> branch nick: 10.0-innodb timestamp: Fri 2014-10-24 17:11:09 +0300 message: MDEV-6934 : os_event_wait_time_low(): wait time calculation is messed up Merged Facebook commit bdab302a7e3c37da21a1bffe1550cdbe6c906695 by Inaam Rana from https://github.com/facebook/mysql-5.6 . In os_event_wait_time_low() the logic to calculate abs_time for wait is broken. The bug has been present at least since 5.5. It gets acutely sensitized when sub-second wait intervals are passed. It is particularly relevant to us because the page_cleaner thread will mostly request sub-second wait intervals. This can potentially lead to a near tight loop behaviour of page_cleaner with much less sleep then what we'd actually expect.

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                • Assignee:
                  jplindst Jan Lindström
                  Reporter:
                  jplindst Jan Lindström
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                    Updated:
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