Run downsampling with ILMedit

This is a simplified example that allows you to see quickly how downsampling works as part of an ILM policy to reduce the storage size of a sampled set of metrics. The example uses typical Kubernetes cluster monitoring data. To test out downsampling with ILM, follow these steps:

Prerequisitesedit

Refer to time series data stream prerequisites.

Before running this example you may want to try the Run downsampling manually example.

Create an index lifecycle policyedit

Create an ILM policy for your time series data. While not required, an ILM policy is recommended to automate the management of your time series data stream indices.

To enable downsampling, add a Downsample action and set fixed_interval to the downsampling interval at which you want to aggregate the original time series data.

In this example, an ILM policy is configured for the hot phase. The downsample takes place after the index is rolled over and the index time series end time has lapsed as the source index is still expected to receive major writes until then. Index lifecycle management will not proceed with any action that expects the index to not receive writes anymore until the index’s end time has passed. The Index lifecycle management actions that wait on the end time before proceeding are: - Delete - Downsample - Force merge - Read only - Searchable snapshot - Shrink

response = client.ilm.put_lifecycle(
  policy: 'datastream_policy',
  body: {
    policy: {
      phases: {
        hot: {
          actions: {
            rollover: {
              max_age: '5m'
            },
            downsample: {
              fixed_interval: '1h'
            }
          }
        }
      }
    }
  }
)
puts response
PUT _ilm/policy/datastream_policy
{
  "policy": {
    "phases": {
      "hot": {
        "actions": {
          "rollover" : {
            "max_age": "5m"
          },
          "downsample": {
  	        "fixed_interval": "1h"
  	      }
        }
      }
    }
  }
}

Create an index templateedit

This creates an index template for a basic data stream. The available parameters for an index template are described in detail in Set up a time series data stream.

For simplicity, in the time series mapping all time_series_metric parameters are set to type gauge, but the counter metric type may also be used. The time_series_metric values determine the kind of statistical representations that are used during downsampling.

The index template includes a set of static time series dimensions: host, namespace, node, and pod. The time series dimensions are not changed by the downsampling process.

response = client.indices.put_index_template(
  name: 'datastream_template',
  body: {
    index_patterns: [
      'datastream*'
    ],
    data_stream: {},
    template: {
      settings: {
        index: {
          mode: 'time_series',
          number_of_replicas: 0,
          number_of_shards: 2
        },
        'index.lifecycle.name' => 'datastream_policy'
      },
      mappings: {
        properties: {
          "@timestamp": {
            type: 'date'
          },
          kubernetes: {
            properties: {
              container: {
                properties: {
                  cpu: {
                    properties: {
                      usage: {
                        properties: {
                          core: {
                            properties: {
                              ns: {
                                type: 'long'
                              }
                            }
                          },
                          limit: {
                            properties: {
                              pct: {
                                type: 'float'
                              }
                            }
                          },
                          nanocores: {
                            type: 'long',
                            time_series_metric: 'gauge'
                          },
                          node: {
                            properties: {
                              pct: {
                                type: 'float'
                              }
                            }
                          }
                        }
                      }
                    }
                  },
                  memory: {
                    properties: {
                      available: {
                        properties: {
                          bytes: {
                            type: 'long',
                            time_series_metric: 'gauge'
                          }
                        }
                      },
                      majorpagefaults: {
                        type: 'long'
                      },
                      pagefaults: {
                        type: 'long',
                        time_series_metric: 'gauge'
                      },
                      rss: {
                        properties: {
                          bytes: {
                            type: 'long',
                            time_series_metric: 'gauge'
                          }
                        }
                      },
                      usage: {
                        properties: {
                          bytes: {
                            type: 'long',
                            time_series_metric: 'gauge'
                          },
                          limit: {
                            properties: {
                              pct: {
                                type: 'float'
                              }
                            }
                          },
                          node: {
                            properties: {
                              pct: {
                                type: 'float'
                              }
                            }
                          }
                        }
                      },
                      workingset: {
                        properties: {
                          bytes: {
                            type: 'long',
                            time_series_metric: 'gauge'
                          }
                        }
                      }
                    }
                  },
                  name: {
                    type: 'keyword'
                  },
                  start_time: {
                    type: 'date'
                  }
                }
              },
              host: {
                type: 'keyword',
                time_series_dimension: true
              },
              namespace: {
                type: 'keyword',
                time_series_dimension: true
              },
              node: {
                type: 'keyword',
                time_series_dimension: true
              },
              pod: {
                type: 'keyword',
                time_series_dimension: true
              }
            }
          }
        }
      }
    }
  }
)
puts response
PUT _index_template/datastream_template
{
    "index_patterns": [
        "datastream*"
    ],
    "data_stream": {},
    "template": {
        "settings": {
            "index": {
                "mode": "time_series",
                "number_of_replicas": 0,
                "number_of_shards": 2
            },
            "index.lifecycle.name": "datastream_policy"
        },
        "mappings": {
            "properties": {
                "@timestamp": {
                    "type": "date"
                },
                "kubernetes": {
                    "properties": {
                        "container": {
                            "properties": {
                                "cpu": {
                                    "properties": {
                                        "usage": {
                                            "properties": {
                                                "core": {
                                                    "properties": {
                                                        "ns": {
                                                            "type": "long"
                                                        }
                                                    }
                                                },
                                                "limit": {
                                                    "properties": {
                                                        "pct": {
                                                            "type": "float"
                                                        }
                                                    }
                                                },
                                                "nanocores": {
                                                    "type": "long",
                                                    "time_series_metric": "gauge"
                                                },
                                                "node": {
                                                    "properties": {
                                                        "pct": {
                                                            "type": "float"
                                                        }
                                                    }
                                                }
                                            }
                                        }
                                    }
                                },
                                "memory": {
                                    "properties": {
                                        "available": {
                                            "properties": {
                                                "bytes": {
                                                    "type": "long",
                                                    "time_series_metric": "gauge"
                                                }
                                            }
                                        },
                                        "majorpagefaults": {
                                            "type": "long"
                                        },
                                        "pagefaults": {
                                            "type": "long",
                                            "time_series_metric": "gauge"
                                        },
                                        "rss": {
                                            "properties": {
                                                "bytes": {
                                                    "type": "long",
                                                    "time_series_metric": "gauge"
                                                }
                                            }
                                        },
                                        "usage": {
                                            "properties": {
                                                "bytes": {
                                                    "type": "long",
                                                    "time_series_metric": "gauge"
                                                },
                                                "limit": {
                                                    "properties": {
                                                        "pct": {
                                                            "type": "float"
                                                        }
                                                    }
                                                },
                                                "node": {
                                                    "properties": {
                                                        "pct": {
                                                            "type": "float"
                                                        }
                                                    }
                                                }
                                            }
                                        },
                                        "workingset": {
                                            "properties": {
                                                "bytes": {
                                                    "type": "long",
                                                    "time_series_metric": "gauge"
                                                }
                                            }
                                        }
                                    }
                                },
                                "name": {
                                    "type": "keyword"
                                },
                                "start_time": {
                                    "type": "date"
                                }
                            }
                        },
                        "host": {
                            "type": "keyword",
                            "time_series_dimension": true
                        },
                        "namespace": {
                            "type": "keyword",
                            "time_series_dimension": true
                        },
                        "node": {
                            "type": "keyword",
                            "time_series_dimension": true
                        },
                        "pod": {
                            "type": "keyword",
                            "time_series_dimension": true
                        }
                    }
                }
            }
        }
    }
}

Ingest time series dataedit

Use a bulk API request to automatically create your TSDS and index a set of ten documents.

Important: Before running this bulk request you need to update the timestamps to within three to five hours after your current time. That is, search 2022-06-21T15 and replace with your present date, and adjust the hour to your current time plus three hours.

response = client.bulk(
  index: 'datastream',
  refresh: true,
  body: [
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:49:00Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 91_153,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 463_314_616
            },
            usage: {
              bytes: 307_007_078,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 585_236
            },
            rss: {
              bytes: 102_728
            },
            pagefaults: 120_901,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:45:50Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 124_501,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 982_546_514
            },
            usage: {
              bytes: 360_035_574,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 1_339_884
            },
            rss: {
              bytes: 381_174
            },
            pagefaults: 178_473,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:44:50Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 38_907,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 862_723_768
            },
            usage: {
              bytes: 379_572_388,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 431_227
            },
            rss: {
              bytes: 386_580
            },
            pagefaults: 233_166,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:44:40Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 86_706,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 567_160_996
            },
            usage: {
              bytes: 103_266_017,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 1_724_908
            },
            rss: {
              bytes: 105_431
            },
            pagefaults: 233_166,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:44:00Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 150_069,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 639_054_643
            },
            usage: {
              bytes: 265_142_477,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 1_786_511
            },
            rss: {
              bytes: 189_235
            },
            pagefaults: 138_172,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:42:40Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 82_260,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 854_735_585
            },
            usage: {
              bytes: 309_798_052,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 924_058
            },
            rss: {
              bytes: 110_838
            },
            pagefaults: 259_073,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:42:10Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 153_404,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 279_586_406
            },
            usage: {
              bytes: 214_904_955,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 1_047_265
            },
            rss: {
              bytes: 91_914
            },
            pagefaults: 302_252,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:40:20Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 125_613,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 822_782_853
            },
            usage: {
              bytes: 100_475_044,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 2_109_932
            },
            rss: {
              bytes: 278_446
            },
            pagefaults: 74_843,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:40:10Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 100_046,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 567_160_996
            },
            usage: {
              bytes: 362_826_547,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 1_986_724
            },
            rss: {
              bytes: 402_801
            },
            pagefaults: 296_495,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    },
    {
      create: {}
    },
    {
      "@timestamp": '2022-06-21T15:38:30Z',
      kubernetes: {
        host: 'gke-apps-0',
        node: 'gke-apps-0-0',
        pod: 'gke-apps-0-0-0',
        container: {
          cpu: {
            usage: {
              nanocores: 40_018,
              core: {
                ns: 12_828_317_850
              },
              node: {
                pct: 2.77905e-05
              },
              limit: {
                pct: 2.77905e-05
              }
            }
          },
          memory: {
            available: {
              bytes: 1_062_428_344
            },
            usage: {
              bytes: 265_142_477,
              node: {
                pct: 0.01770037710617187
              },
              limit: {
                pct: 9.923134671484496e-05
              }
            },
            workingset: {
              bytes: 2_294_743
            },
            rss: {
              bytes: 340_623
            },
            pagefaults: 224_530,
            majorpagefaults: 0
          },
          start_time: '2021-03-30T07:59:06Z',
          name: 'container-name-44'
        },
        namespace: 'namespace26'
      }
    }
  ]
)
puts response
PUT /datastream/_bulk?refresh
{"create": {}}
{"@timestamp":"2022-06-21T15:49:00Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":91153,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":463314616},"usage":{"bytes":307007078,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":585236},"rss":{"bytes":102728},"pagefaults":120901,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:45:50Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":124501,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":982546514},"usage":{"bytes":360035574,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":1339884},"rss":{"bytes":381174},"pagefaults":178473,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:44:50Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":38907,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":862723768},"usage":{"bytes":379572388,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":431227},"rss":{"bytes":386580},"pagefaults":233166,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:44:40Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":86706,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":567160996},"usage":{"bytes":103266017,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":1724908},"rss":{"bytes":105431},"pagefaults":233166,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:44:00Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":150069,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":639054643},"usage":{"bytes":265142477,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":1786511},"rss":{"bytes":189235},"pagefaults":138172,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:42:40Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":82260,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":854735585},"usage":{"bytes":309798052,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":924058},"rss":{"bytes":110838},"pagefaults":259073,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:42:10Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":153404,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":279586406},"usage":{"bytes":214904955,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":1047265},"rss":{"bytes":91914},"pagefaults":302252,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:40:20Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":125613,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":822782853},"usage":{"bytes":100475044,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":2109932},"rss":{"bytes":278446},"pagefaults":74843,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:40:10Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":100046,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":567160996},"usage":{"bytes":362826547,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":1986724},"rss":{"bytes":402801},"pagefaults":296495,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}
{"create": {}}
{"@timestamp":"2022-06-21T15:38:30Z","kubernetes":{"host":"gke-apps-0","node":"gke-apps-0-0","pod":"gke-apps-0-0-0","container":{"cpu":{"usage":{"nanocores":40018,"core":{"ns":12828317850},"node":{"pct":2.77905e-05},"limit":{"pct":2.77905e-05}}},"memory":{"available":{"bytes":1062428344},"usage":{"bytes":265142477,"node":{"pct":0.01770037710617187},"limit":{"pct":9.923134671484496e-05}},"workingset":{"bytes":2294743},"rss":{"bytes":340623},"pagefaults":224530,"majorpagefaults":0},"start_time":"2021-03-30T07:59:06Z","name":"container-name-44"},"namespace":"namespace26"}}

View the resultsedit

Now that you’ve created and added documents to the data stream, check to confirm the current state of the new index.

response = client.indices.get_data_stream
puts response
GET _data_stream

If the ILM policy has not yet been applied, your results will be like the following. Note the original index_name: .ds-datastream-<timestamp>-000001.

{
  "data_streams": [
    {
      "name": "datastream",
      "timestamp_field": {
        "name": "@timestamp"
      },
      "indices": [
        {
          "index_name": ".ds-datastream-2022.08.26-000001",
          "index_uuid": "5g-3HrfETga-5EFKBM6R-w"
        },
        {
          "index_name": ".ds-datastream-2022.08.26-000002",
          "index_uuid": "o0yRTdhWSo2pY8XMvfwy7Q"
        }
      ],
      "generation": 2,
      "status": "GREEN",
      "template": "datastream_template",
      "ilm_policy": "datastream_policy",
      "hidden": false,
      "system": false,
      "allow_custom_routing": false,
      "replicated": false,
      "rollover_on_write": false,
      "time_series": {
        "temporal_ranges": [
          {
            "start": "2022-08-26T13:29:07.000Z",
            "end": "2022-08-26T19:29:07.000Z"
          }
        ]
      }
    }
  ]
}

Next, run a search query:

response = client.search(
  index: 'datastream'
)
puts response
GET datastream/_search

The query returns your ten newly added documents.

{
  "took": 17,
  "timed_out": false,
  "_shards": {
    "total": 4,
    "successful": 4,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": {
      "value": 10,
      "relation": "eq"
    },
...

By default, index lifecycle management checks every ten minutes for indices that meet policy criteria. Wait for about ten minutes (maybe brew up a quick coffee or tea ☕ ) and then re-run the GET _data_stream request.

response = client.indices.get_data_stream
puts response
GET _data_stream

After the ILM policy has taken effect, the original .ds-datastream-2022.08.26-000001 index is replaced with a new, downsampled index, in this case downsample-6tkn-.ds-datastream-2022.08.26-000001.

{
  "data_streams": [
    {
      "name": "datastream",
      "timestamp_field": {
        "name": "@timestamp"
      },
      "indices": [
        {
          "index_name": "downsample-6tkn-.ds-datastream-2022.08.26-000001",
          "index_uuid": "qRane1fQQDCNgKQhXmTIvg"
        },
        {
          "index_name": ".ds-datastream-2022.08.26-000002",
          "index_uuid": "o0yRTdhWSo2pY8XMvfwy7Q"
        }
      ],
...

Run a search query on the datastream (note that when querying downsampled indices there are a few nuances to be aware of).

response = client.search(
  index: 'datastream'
)
puts response
GET datastream/_search

The new downsampled index contains just one document that includes the min, max, sum, and value_count statistics based off of the original sampled metrics.

{
  "took": 6,
  "timed_out": false,
  "_shards": {
    "total": 4,
    "successful": 4,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": {
      "value": 1,
      "relation": "eq"
    },
    "max_score": 1,
    "hits": [
      {
        "_index": "downsample-6tkn-.ds-datastream-2022.08.26-000001",
        "_id": "0eL0wC_4-45SnTNFAAABgtpz0wA",
        "_score": 1,
        "_source": {
          "@timestamp": "2022-08-26T14:00:00.000Z",
          "_doc_count": 10,
          "kubernetes.host": "gke-apps-0",
          "kubernetes.namespace": "namespace26",
          "kubernetes.node": "gke-apps-0-0",
          "kubernetes.pod": "gke-apps-0-0-0",
          "kubernetes.container.cpu.usage.nanocores": {
            "min": 38907,
            "max": 153404,
            "sum": 992677,
            "value_count": 10
          },
          "kubernetes.container.memory.available.bytes": {
            "min": 279586406,
            "max": 1062428344,
            "sum": 7101494721,
            "value_count": 10
          },
          "kubernetes.container.memory.pagefaults": {
            "min": 74843,
            "max": 302252,
            "sum": 2061071,
            "value_count": 10
          },
          "kubernetes.container.memory.rss.bytes": {
            "min": 91914,
            "max": 402801,
            "sum": 2389770,
            "value_count": 10
          },
          "kubernetes.container.memory.usage.bytes": {
            "min": 100475044,
            "max": 379572388,
            "sum": 2668170609,
            "value_count": 10
          },
          "kubernetes.container.memory.workingset.bytes": {
            "min": 431227,
            "max": 2294743,
            "sum": 14230488,
            "value_count": 10
          },
          "kubernetes.container.cpu.usage.core.ns": 12828317850,
          "kubernetes.container.cpu.usage.limit.pct": 0.000027790500098490156,
          "kubernetes.container.cpu.usage.node.pct": 0.000027790500098490156,
          "kubernetes.container.memory.majorpagefaults": 0,
          "kubernetes.container.memory.usage.limit.pct": 0.00009923134348355234,
          "kubernetes.container.memory.usage.node.pct": 0.017700377851724625,
          "kubernetes.container.name": "container-name-44",
          "kubernetes.container.start_time": "2021-03-30T07:59:06.000Z"
        }
      }
    ]
  }
}

Use the data stream stats API to get statistics for the data stream, including the storage size.

response = client.indices.data_streams_stats(
  name: 'datastream',
  human: true
)
puts response
GET /_data_stream/datastream/_stats?human=true
{
  "_shards": {
    "total": 4,
    "successful": 4,
    "failed": 0
  },
  "data_stream_count": 1,
  "backing_indices": 2,
  "total_store_size": "16.6kb",
  "total_store_size_bytes": 17059,
  "data_streams": [
    {
      "data_stream": "datastream",
      "backing_indices": 2,
      "store_size": "16.6kb",
      "store_size_bytes": 17059,
      "maximum_timestamp": 1661522400000
    }
  ]
}

This example demonstrates how downsampling works as part of an ILM policy to reduce the storage size of metrics data as it becomes less current and less frequently queried.

You can also try our Run downsampling manually example to learn how downsampling can work outside of an ILM policy.