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  1. WiredTiger
  2. WT-4307

Mitigate overhead from copying keys when creating transaction op structure

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Details

    • Bug
    • Status: Closed
    • Major - P3
    • Resolution: Done
    • None
    • None
    • None
    • 1
    • Storage Engines 2018-09-24, Storage Engines 2018-10-08

    Description

      In order to support long running prepared transactions, we allow pages with prepared updates to be evicted. To support that, we need to know the key when resolving a prepared transaction to find the update in the lookaside file again.

      We recently introduced code to always copy the key when populating a WT_TXN_OP structure - that adds a performance penalty for transactions that never prepare, since their updates can't be evicted.

      We should investigate paths to avoid the copy in the common case.

      Attachments

        Issue Links

          is caused by

          Task - A task that needs to be done. WT-4246 Change transaction update list to support indirect references

          • Major - P3 - Major loss of function.
          • Closed
          is depended on by

          Task - A task that needs to be done. WT-4220 Enable long running prepared support

          • Major - P3 - Major loss of function.
          • Closed
          is related to

          New Feature - A new feature of the product, which has yet to be developed. WT-4305 Add a gating variable for long running prepare support

          • Major - P3 - Major loss of function.
          • Closed

          Activity

            People

              sulabh.mahajan@mongodb.com Sulabh Mahajan
              alexander.gorrod@mongodb.com Alexander Gorrod
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                Updated:
                Resolved: