概述

继续跟中华石杉老师学习ES，第48篇

课程地址： https://www.roncoo.com/view/55

官方说明

Percentiles Aggregation：戳这里

示例

需求：网站访问时延统计

为了演示该功能，我们先建个索引，模拟一批数据

#新建索引
PUT /website
{
  "mappings": {
    "logs": {
      "properties": {
        "latency": {
          "type": "long"
        },
        "province": {
          "type": "keyword"
        },
        "timestamp": {
          "type": "date"
        }
      }
    }
  }
}

#模拟数据
POST /website/logs/_bulk
{ "index": {}}
{ "latency" : 105, "province" : "江苏", "timestamp" : "2018-10-28" }
{ "index": {}}
{ "latency" : 83, "province" : "江苏", "timestamp" : "2018-10-29" }
{ "index": {}}
{ "latency" : 92, "province" : "江苏", "timestamp" : "2018-10-29" }
{ "index": {}}
{ "latency" : 112, "province" : "江苏", "timestamp" : "2018-10-28" }
{ "index": {}}
{ "latency" : 68, "province" : "江苏", "timestamp" : "2018-10-28" }
{ "index": {}}
{ "latency" : 76, "province" : "江苏", "timestamp" : "2018-10-29" }
{ "index": {}}
{ "latency" : 101, "province" : "新疆", "timestamp" : "2018-10-28" }
{ "index": {}}
{ "latency" : 275, "province" : "新疆", "timestamp" : "2018-10-29" }
{ "index": {}}
{ "latency" : 166, "province" : "新疆", "timestamp" : "2018-10-29" }
{ "index": {}}
{ "latency" : 654, "province" : "新疆", "timestamp" : "2018-10-28" }
{ "index": {}}
{ "latency" : 389, "province" : "新疆", "timestamp" : "2018-10-28" }
{ "index": {}}
{ "latency" : 302, "province" : "新疆", "timestamp" : "2018-10-29" }

DSL:

#网站访问时延统计（50% 95% 99%的请求）
GET /website/logs/_search
{
  "size": 0,
  "aggs": {
    "latency_percentiles": {
      "percentiles": {
        "field": "latency",
        "percents": [
          50,
          95,
          99
        ]
      }
    },
    "latency_avg": {
      "avg": {
        "field": "latency"
      }
    }
  }
}

{
  "took": 3,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 12,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "latency_avg": {
      "value": 201.91666666666666
    },
    "latency_percentiles": {
      "values": {
        "50.0": 108.5,
        "95.0": 627.4999999999997,
        "99.0": 654
      }
    }
  }
}

可知,

50%的请求在 108.5毫秒
95%的请求在 627.5毫秒
99%的请求在 654毫秒
平均时延 201.9毫秒

数值的最大的值是多少，不是完全准确的

需求二：按地区分组后看下每个地区的网站访问时延统计

GET /website/_search
{
  "size": 0,
  "aggs": {
    "group_by_province": {
      "terms": {
        "field": "province"
      },
      "aggs": {
        "latency_percentiles": {
          "percentiles": {
            "field": "latency",
            "percents": [
              50,
              95,
              99
            ]
          }
        },
        "latency_avg": {
          "avg": {
            "field": "latency"
          }
        }
      }
    }
  }
}