TimeoutException搜索RestHighLevelClient (6.0.0) --运行时的Elasticsearch

Question

我们的应用程序在索引(存储) elasticsearch服务器中的文档时出现encoutner超时异常。它并不经常发生，但大约一天一次。以下是详细信息。

pom.xml

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>6.0.0</version>
</dependency>

初始化

@Bean
public RestHighLevelClient buildHighLevelClient() {
    RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(httplist.toArray(new HttpHost[]{})));
    return client;
}

异常信息

java.lang.RuntimeException: error while performing request
at org.elasticsearch.client.RestClient$SyncResponseListener.get(RestClient.java:682)
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:220)
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:192)
at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:428)
at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:414)
at org.elasticsearch.client.RestHighLevelClient.bulk(RestHighLevelClient.java:229)
......
Caused by: java.util.concurrent.TimeoutException
at org.apache.http.nio.pool.AbstractNIOConnPool.processPendingRequest(AbstractNIOConnPool.java:364)
at org.apache.http.nio.pool.AbstractNIOConnPool.processNextPendingRequest(AbstractNIOConnPool.java:344)
at org.apache.http.nio.pool.AbstractNIOConnPool.release(AbstractNIOConnPool.java:318)
at org.apache.http.impl.nio.conn.PoolingNHttpClientConnectionManager.releaseConnection(PoolingNHttpClientConnectionManager.java:303)
at org.apache.http.impl.nio.client.AbstractClientExchangeHandler.releaseConnection(AbstractClientExchangeHandler.java:239)

Answer 1

我使用以下设置解决了这个问题：

RestClientBuilder builder = RestClient.builder(
      new HttpHost("localhost", 9200, "http")); builder.setRequestConfigCallback(
      new RestClientBuilder.RequestConfigCallback() {
         @Override
         public RequestConfig.Builder customizeRequestConfig(
                 RequestConfig.Builder requestConfigBuilder) {
             return requestConfigBuilder.setConnectionRequestTimeout(-1); 
         }
     });

底层Apache的RestClient在其连接池中有一个限制为AFAIK10并发连接。因此，如果并发请求超过10个，则额外的请求将排队，并可能命中org.elasticsearch.client.RestClientBuilder中设置的默认DEFAULT_CONNECTION_REQUEST_TIMEOUT_MILLIS = 500;