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  1. Couchbase Server
  2. MB-20285

4x higher latency in view query tests with reducers

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Details

    • Bug
    • Resolution: Fixed
    • Major
    • 5.0.0
    • 5.0.0
    • view-engine
    • Hellios: 1 node, CentOS 7, E5-4610 (48 vCPU), 256 GB, SSD
    • Yes

    Description

      While latency has decreased in all other scenarios (see ShowFast), latency in "group by" case has increased significantly.

      The following views are used in this scenario:

      # ############################## GROUP ############################## #
              'group_by': {
                  'coins_stats_by_state_and_year': {
                      'map': '''
                          function(doc, meta) {
                              emit(
                                  [
                                      doc.state.f,
                                      doc.year
                                  ],
                                  doc.coins.f
                              );
                          }
                      ''',
                      'reduce': '_stats',
                  },
                  'coins_stats_by_gmtime_and_year': {
                      'map': '''
                          function(doc, meta) {
                              emit(
                                  [doc.gmtime, doc.year],
                                  doc.coins.f
                              );
                          }
                      ''',
                      'reduce': '_stats',
                  },
                  'coins_stats_by_full_state_and_year': {
                      'map': '''
                          function(doc, meta) {
                              emit(
                                  [
                                      doc.full_state.f,
                                      doc.year
                                  ],
                                  doc.coins.f
                              );
                          }
                      ''',
                      'reduce': '_stats',
                  },
              },
      

      https://github.com/couchbase/perfrunner/blob/master/perfrunner/workloads/viewgen.py#L198

      Workload configuration:

      • 20M docs, 1KB size
      • 100 updates / sec
      • <100 queries / sec
      • stale=false queries

      Sample document:

      {
        "category": 1,
        "city": {
          "f": {
            "f": "858033"
          }
        },
        "capped_large": "3000_0",
        "realm": {
          "f": "ca023c"
        },
        "name": {
          "f": {
            "f": {
              "f": "f42ddd a8fec8"
            }
          }
        },
        "capped_small": "100_0",
        "country": {
          "f": "e78404"
        },
        "coins": {
          "f": 256.07
        },
        "body": "f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e78404e10d8c1c2c6b46a3f42ddda8fec8531f45cee8ae858033ca023c6407d7e784",
        "gmtime": [
          1973,
          4,
          3,
          0,
          0,
          0,
          1,
          93,
          0
        ],
        "county": {
          "f": {
            "f": "e10d8c"
          }
        },
        "state": {
          "f": "OH"
        },
        "street": {
          "f": {
            "f": "1c2c6b46"
          }
        },
        "alt_email": {
          "f": {
            "f": "fec853@f45cee.com"
          }
        },
        "year": 1995,
        "full_state": {
          "f": "Connecticut"
        },
        "achievements": [
          7,
          87,
          219,
          231,
          83
        ],
        "email": {
          "f": {
            "f": "531f45@cee8ae.com"
          }
        }
      }
      

      Logs, build 844: http://perf.jenkins.couchbase.com/view/Weekly%20Linux/job/helios/1665/artifact/
      Logs, build 854: http://perf.jenkins.couchbase.com/view/Weekly%20Linux/job/helios/1666/artifact/

      Graphs: http://cbmonitor.sc.couchbase.com/reports/html/?snapshot=helios_470-854_241_access

      Attachments

        Issue Links

          For Gerrit Dashboard: MB-20285
          # Subject Branch Project Status CR V

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              harsha Harsha Havanur
              pavelpaulau Pavel Paulau (Inactive)
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              Dates

                Created:
                Updated:
                Resolved:

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