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  1. MariaDB ColumnStore
  2. MCOL-1758

TupleJoiner allocates too much RAM

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Details

    • Bug
    • Status: Closed (View Workflow)
    • Major
    • Resolution: Fixed
    • None
    • 1.4.1
    • None
    • None
    • 2019-06

    Description

      Every TupleJoiner thread pre-allocates 64MB using our STLPoolAllocator class. With our thread pool that can spawn many threads very quickly pre-allocating a lot of memory. In some systems this will easily blow the configured overcommit. In my tests running 20 simple simultaneous queries it hit 32GB of allocation with only about 1% of that actually used.

      Our STLPoolAllocator class also isn't a pool (it isn't even thread safe so it can't be). We would be likely better off using boost::pool_allocator or another off-the-shelf singleton pool allocator.

      Attachments

        1. stack.pdf
          17 kB
        2. 1.4.1-1.pdf
          25 kB
        3. 1.2.5-1.pdf
          19 kB

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          People

            dleeyh Daniel Lee (Inactive)
            LinuxJedi Andrew Hutchings (Inactive)
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            Dates

              Created:
              Updated:
              Resolved:

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