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  1. MariaDB Server
  2. MDEV-22242

B-trees can become extremely skewed

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      The test innodb.innodb_wl6326 that was disabled in 10.4 due to failures caused by MDEV-21535 is failing on 10.5 due to another reason: the removal of the MLOG_COMP_END_COPY_CREATED operations in MDEV-12353 caused PAGE_LAST_INSERT to be set to something nonzero by the function page_copy_rec_list_end().

      This in turn would cause btr_page_get_split_rec_to_right() to behave differently: we would not attempt to split the page at all, but simply insert the new record into the new, empty, right leaf page.

      Even though the change reduced the sizes of some tables, it is better to aim for balanced trees.

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          is caused by

          Task - A task that needs to be done. MDEV-12353 Efficient InnoDB redo log record format

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed
          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-21535 Unnecessarily large ha_innobase::records_in_range() scans

          • Major - Major loss of function.
          • Closed

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              marko Marko Mäkelä
              marko Marko Mäkelä
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                Resolved:

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