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  1. Phoenix
  2. PHOENIX-1121 Improve tracing in Phoenix
  3. PHOENIX-2178

Tracing - total time listed for a certain trace does not correlate with query wall clock time

    Details

    • Type: Sub-task
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: 4.5.0
    • Fix Version/s: None
    • Labels:

      Description

      Wall clock for a count * takes over a large table takes 30000+ms however total sum(end_time - start_time) is less than 250ms for trace_id generated for this count * query.

      Output of trace table:
      
      select sum(end_time  - start_time),count(*), description from SYSTEM.TRACING_STATS WHERE TRACE_ID=X group by description;
      +------------------------------------------+------------------------------------------+------------------------------------------+
      |       SUM((END_TIME - START_TIME))       |                 COUNT(1)                 |               DESCRIPTION                |
      +------------------------------------------+------------------------------------------+------------------------------------------+
      | 0                                        | 3                                        | ClientService.Scan                       |
      | 240                                      | 253879                                   | HFileReaderV2.readBlock                  |
      | 1                                        | 1                                        | Scanner opened on server                 |
      +------------------------------------------+------------------------------------------+------------------------------------------+
      
      

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              • Assignee:
                Unassigned
                Reporter:
                mujtabachohan Mujtaba Chohan
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                Dates

                • Created:
                  Updated: