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  1. MariaDB ColumnStore
  2. MCOL-5187

OOM happening when querying large datasets and using distinct

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    Details

    • Type: Bug
    • Status: In Progress (View Workflow)
    • Priority: Critical
    • Resolution: Unresolved
    • Affects Version/s: 22.08.1, 6.4.6
    • Fix Version/s: 23.02
    • Component/s: None
    • Labels:
    • Environment:
      ububts 20.04 LTS

      Description

      I set TotalUmMemory to 25%, but ExeMgr use far beyond usage memory.
      Finally ExeMgr was killed by oom-killer.
      I tried two sql on large datasets.

      1. select distinct columnA, columnB, columnC from table.
      2. select columnA, columnB, columnC from table group by columnA, columnB, columnC.

      1. is OOM,
      but 2. is MCS-2003: Aggregation/Distinct memory limit is exceeded.

      I think 1. and 2. are similar query.
      I think that 1. should return same message (MCS-2003: Aggregation/Distinct memory limit is exceeded.)

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              Assignee:
              drrtuy Roman
              Reporter:
              Atsushi Kugimiya
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                Dates

                Created:
                Updated:

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