es相关优化

首先得认识到：
Max number of nodes = Number of shards * (number of replicas +1)，也就是说节点的最大数量=分片数*（分片副本+1），其中number of replicas是指为每个副本设置几个分片副本（也就是备份）。过多的分配分片副本，会消耗磁盘空间，对于服务器的新能有很大的影响，如果我为每个shard都分配一个replica，那么最多消耗20个节点，索引创建格式一般:
curl -XPUT localhost:9200/{index}/{type}/{id},比如：

[root@centos2 elasticsearch-5.1.2]# curl   -XPUT  192.168.220.130:9200/7777/blog/123  -d'{
  
  "title": "My first blog entry",
  "text":  "Just trying this out...",
  "date":  "2014/01/01"
}'

插件上对应的位置是：

image.png

。
对于一般情况下，如果对es集群不进行一些设置，节点的服务关闭，会影响到分片数据不完整，导致搜索到的数据不完整，如下开启2个es节点，创建索引和分片：

curl -XPUT localhost:9200/documents -d '{
settings: {
number_of_replicas: 0,
number_of_shards: 2
}
}'

这里创建了2个分片，0个分片副本，根据上面的公式，最多有2个node节点，然后往节点里放入数据：

curl -XPUT  localhost:9200/documents/doc/1 -d '{ "title" : "Document No. 1" }'
curl -XPUT  localhost:9200/documents/doc/2 -d '{ "title" : "Document No. 2" }'
curl -XPUT  localhost:9200/documents/doc/3 -d '{ "title" : "Document No. 3" }'
curl -XPUT  localhost:9200/documents/doc/3 -d '{ "title" : "Document No. 4" }'

这里我创建个测试的索引111，命令行创建111索引命令如下：

[root@centos2 elasticsearch-5.1.2]# curl -XPUT 192.168.220.130:9200/1111  -d '{"settings" : {"index" : {"number_of_shards" : 3,"number_of_replicas" : 2}}}'
执行结果如下：
{"acknowledged":true,"shards_acknowledged":true}

图片.png

创建了3个索引，并且每一个索引都有2个分片副本（备份)，获取索引信息：

[root@centos2 elasticsearch-5.1.2]# curl -XGET 192.168.220.130:9200/1111  
{"1111":{"aliases":{},"mappings":{},"settings":{"index":{"creation_date":"1503138217545","number_of_shards":"3","number_of_replicas":"2","uuid":"bMffoqpORdOQ-_LQlwJsRA","version":{"created":"5010299"},"provided_name":"1111"}}}}[root@centos2 elasticsearch-5.1.2]# 

创建索引并制定map

curl -XPUT 192.168.220.130:9200/1111  -d'{
    "settings" : {
        "number_of_shards" : 1
    },
    "mappings" : {
        "type1" : {
            "properties" : {
                "field1" : { "type" : "text" }
            }
        }
    }
}'

关闭索引：

[root@centos2 elasticsearch-5.1.2]# curl -XPOST 192.168.220.130:9200/1111/_close
{"acknowledged":true}[root@centos2 elasticsearch-5.1.2]# 

图片.png

打开索引：
curl -XPOST 192.168.220.130:9200/1111/_open

设置mapping：
这个可以给索引或者字段增加type的maping，如下我创建db索引：

curl -XPOST 192.168.220.130:9200/gb/tweet  -d'{
   "gb": {
      "mappings": {
         "tweet": {
            "properties": {
               "date": {
                  "type": "date",
                  "format": "strict_date_optional_time||epoch_millis"
               },
               "name": {
                  "type": "string"
               },
               "tweet": {
                  "type": "string"
               },
               "user_id": {
                  "type": "long"
               }
            }
         }
      }
   }
}'

这里我给新创建的索引的type设置成了tweet，反应在页面如下：

图片.png

设置主分片以及副本分片数量，要去更改配置文件：
index.number_of_shards: 5
设置默认索引分片个数，默认为5片。
index.number_of_replicas: 1
设置默认索引副本个数，默认为1个副本。

索引删除：

[root@centos2 elasticsearch-5.1.2]# curl   -XDELETE  192.168.220.130:9200/6666666/blog/123/  -d'{
  
  "title": "My first blog entry",
  "text":  "Just trying this out...",
  "date":  "2014/01/01"
}'
{"found":true,"_index":"6666666","_type":"blog","_id":"123","_version":4,"result":"deleted","_shards":{"total":2,"successful":1,"failed":0}}[root@centos2 elasticsearch-5.1.2]# curl   -XDELETE  192.168.220.130:9200/6666666/b^C
[root@centos2 elasticsearch-5.1.2]# curl   -XDELETE  192.168.220.130:9200/6666666/blog/123/  -d'{
  
  "title": "My first blog entry",
  "text":  "Just trying this out...",
  "date":  "2014/01/01"
}'
{"found":false,"_index":"6666666","_type":"blog","_id":"123","_version":5,"result":"not_found","_shards":{"total":2,"successful":1,"failed":0}}[root@centos2 elasticsearch-5.1.2]# ^C
```我们看到fonud返回值已经是false,并且"_version"的值还在增加，这样删除了该索引，只不过插件展示上会有延迟。


官网地址：https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-stats.html
http://blog.csdn.net/napoay/article/details/73251965
https://wizardforcel.gitbooks.io/mastering-elasticsearch/content/chapter-4/42_README.html