Elasticsearch初始化配置

构建ES集群环境经常用到的配置：
1.action.auto_create_index --配置是否自动创建索引（true OR false);
2.gateway.type -- (fs, none, local);
3.cluster.routing.schedule 如（50ms)， 发现新节点时间


Settings settings = settingsBuilder()
                .put("discovery.type", "zen") //发现集群方式
                .put("discovery.zen.minimum_master_nodes", 2) //最少有2个master存在
                .put("discovery.zen.ping_timeout", "200ms") //集群ping时间，太小可能会因为网络通信而导致不能发现集群
                .put("discovery.initial_state_timeout", "500ms")
                .put("gateway.type", "local")
                .put("index.number_of_shards", 1)
                .put("action.auto_create_index", false)
                .put("cluster.routing.schedule", "50ms")
                .build();


改变shards数目：

client.admin().indices().prepareUpdateSettings("test").setSettings(settingsBuilder().put("index.number_of_replicas", 2)).execute().actionGet();

使用Mongodb River时，可设置 river.mongodb: TRACE 打开日志。

ES常量设置：
index.cache.query.parser.type 查询分析缓存类型， 分为：JVM级别， resident的和NULL。
index.cache.field.max_size 设置大小，配置为soft时用。
index.cache.field.expire 可设置为null,表示永不过期。
index.cache.field.type 值集合：{resident, soft, none} 分别为常驻式、驱逐式、无缓存
index.cache.filter.type (none, weighted)
index.codec.postings_format.type (BloomFilterPostingsFormatProvider,DirectPostingsFormatProvider, MemoryPostingsFormatProvider, Lucene40PostingsFormatProvider, Pulsing40PostingsFormatProvider)
cluster.routing.operation.type
cluster.routing.operation.hash.type （DjbHashFunction， SimpleHashFunction）
index.analysis.char_filter
index.cache.id.type (SimpleIdCache)

index.merge.policy.type 
                "index.merge.policy.min_merge_size",
                "index.merge.policy.max_merge_size",
                "index.merge.policy.max_merge_docs",
                "index.merge.policy.merge_factor",
                "index.compound_format"

                "index.merge.policy.min_merge_docs",
                "index.merge.policy.max_merge_docs",
                "index.merge.policy.merge_factor",
                "index.compound_format"

                "index.merge.policy.expunge_deletes_allowed",
                "index.merge.policy.floor_segment",
                "index.merge.policy.max_merge_at_once",
                "index.merge.policy.max_merge_at_once_explicit",
                "index.merge.policy.max_merged_segment",
                "index.merge.policy.segments_per_tier",
                "index.merge.policy.reclaim_deletes_weight",
                "index.compound_format"

index.merge.scheduler.type

index.similarity.type
monitor.dump.type

cluster.routing.operation.type
index.engine.type
index.store.type (ram, memory, fs, simplefs, niofs, mmapfs)
transport.type