Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: Impala 2.0
    • Fix Version/s: Impala 2.0.1
    • Component/s: None
    • Labels:
      None
    • Environment:
      CDH 5.2.0, CentOS

      Description

      Memory usage grows rapidly while scanning a large table (multi TB) using upper() or lower() function on a string column, and the query terminates with "Memory Limit Exceeded" error.

      Memory leak happens when executing:
      select * from table_name where lower(column_name) = "condition";
      select * from table_name where upper(column_name) = "CONDITION";
      Even worse if I put more similar conditions in a single query.

      However, queries like these are fine:
      select * from table_name where column_name = "condition";
      select * from table_name where column_name like "%condition%";

      Not sure whether other functions have the same problem.

        Attachments

        1. impala.zip
          130 kB
          S Y Zhang
        2. mem.png
          7 kB
          S Y Zhang
        3. profile.txt
          106 kB
          S Y Zhang

          Activity

            People

            • Assignee:
              skye Skye Wanderman-Milne
              Reporter:
              dfxbb S Y Zhang
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              Dates

              • Created:
                Updated:
                Resolved: