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  1. Kudu
  2. KUDU-1801

High lock contention on TableInfo objects

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 1.2.0
    • Component/s: master
    • Labels:
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    • Target Version/s:

      Description

      In an Impala test on a 200-node cluster with 40 concurrent query streams, I see the master has high contention on TableInfo::lock_. Two issues seem to be at play:
      1) we could easily swap it for a rwlock for a big win, since it's a read-mostly structure
      2) GetTableSchema() calls IsCreateTableDone() which is O in the number of tablets. For each tablet, we acquire its rwc lock, so the iteration isn't cheap. The table-wide "create table done" state seems quite cacheable.

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            • Assignee:
              tlipcon Todd Lipcon
              Reporter:
              tlipcon Todd Lipcon
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                Updated:
                Resolved: