環(huán)境配置

• ES版本：5.4.3
• 系統(tǒng):CentOS release 6.x
• spring-data-elasticsearch:3.0.0.RELEASE
• spring:5.0.1.RELEASE

問題

1.本地訪問es的restful接口不通

需要更改下面配置（elasticsearch.yml）：

network.bind_host:0.0.0.0
network.host: <服務(wù)器ip>

如果系統(tǒng)是CentOS release 6.x的，需要在(elasticsearch.yml)增加下面語句

bootstrap.memory_lock: false
bootstrap.system_call_filter: false

2.max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]

需要修改linux的內(nèi)核設(shè)置，在/etc/sysctl.conf文件加入

vm.max_map_count=262144

然后系統(tǒng)執(zhí)行：

sysctl -p

3.availableProcessors is already set to

Caused by: java.lang.IllegalStateException: availableProcessors is already set to [4], rejecting [4]
    at io.netty.util.NettyRuntime$AvailableProcessorsHolder.setAvailableProcessors(NettyRuntime.java:51)
    at io.netty.util.NettyRuntime.setAvailableProcessors(NettyRuntime.java:87)
    at org.elasticsearch.transport.netty4.Netty4Utils.setAvailableProcessors(Netty4Utils.java:82)
    at org.elasticsearch.transport.netty4.Netty4Transport.<init>(Netty4Transport.java:138)
    at org.elasticsearch.transport.Netty4Plugin.lambda$getTransports$0(Netty4Plugin.java:93)
    at org.elasticsearch.client.transport.TransportClient.buildTemplate(TransportClient.java:174)
    at org.elasticsearch.client.transport.TransportClient.<init>(TransportClient.java:265)
    at org.elasticsearch.transport.client.PreBuiltTransportClient.<init>(PreBuiltTransportClient.java:130)
    at org.elasticsearch.transport.client.PreBuiltTransportClient.<init>(PreBuiltTransportClient.java:116)
    at org.elasticsearch.transport.client.PreBuiltTransportClient.<init>(PreBuiltTransportClient.java:106)
    at org.springframework.data.elasticsearch.client.TransportClientFactoryBean.buildClient(TransportClientFactoryBean.java:91)
    at org.springframework.data.elasticsearch.client.TransportClientFactoryBean.afterPropertiesSet(TransportClientFactoryBean.java:86)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1763)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1700)
    ... 82 more

解決辦法：

@Slf4j
@Component
public class ElasticSearchConfiguration implements InitializingBean {

    static {
        System.setProperty("es.set.netty.runtime.available.processors", "false");
    }


    @Override
    public void afterPropertiesSet() throws Exception {
        log.info("*****************es_config*************************");
        log.info("es.set.netty.runtime.available.processors:{}", System.getProperty("es.set.netty.runtime.available.processors"));
        log.info("***************************************************");
    }
}

原因是Lucene改進(jìn)了數(shù)值類型的索引數(shù)據(jù)結(jié)構(gòu)，使用了block k-d 樹。這種樹的葉結(jié)點(diǎn)上文檔不是有序排列的，所以查詢的時(shí)候需要獲取所有的文檔id，訪問 docValues構(gòu)造 bitset，進(jìn)行其它條件的聯(lián)合查詢。當(dāng)查詢的結(jié)果集很大的時(shí)候，大量時(shí)間會(huì)用于構(gòu)造bitset，導(dǎo)致了慢查詢。

解決方式：在不需要進(jìn)行 rangeQuery 的時(shí)候，盡量不要選擇數(shù)值類型作為存儲(chǔ)格式，使用 keyword 替代，尤其是在重復(fù)值數(shù)量很大的時(shí)候。

https://elasticsearch.cn/article/446