Liu Zhao created KYLIN-5539: ------------------------------- Summary: Kylin4 JobServer在每次Cube构建后未关闭已打开的HDFS文件流,产生大量CLOSE_WAIT Key: KYLIN-5539 URL: https://issues.apache.org/jira/browse/KYLIN-5539 Project: Kylin Issue Type: Bug Components: Job Engine Affects Versions: v4.0.3, v4.0.2, v4.0.1 Reporter: Liu Zhao
1.初始发现:线上告警某节点存在大量的CLOSE_WAIT,通过 netstat -anp 发现来自与Kylin4 JobServer 进程,CLOSE_WAIT数达到9000多。并且 CLOSE_WAIT 来自的外部地址端口都是 50010,而改端口是 Hadoop DataNode 数据传输使用,故此怀疑是 JobServer在每次作业构建时 fileSystem.open() 一个流后没有进行close。 2.模拟复现:在研测环境提交cube构建任务,并观察 CLOSE_WAIT 数及增长情况,发现每次cube构建结束后,CLOSE_WAIT 数增加1,至此可以确定时JobServer代码中未关闭流导致。 3.定位代码:深入kylin4 构建代码进行debug,最终定位到 org.apache.kylin.engine.spark.utils.UpdateMetadataUtil#syncLocalMetadataToRemote 94行 (Apache Kylin main分支) String resKey = toUpdateSeg.getStatisticsResourcePath(); String statisticsDir = config.getJobTmpDir(currentInstanceCopy.getProject()) + "/" + nsparkExecutable.getParam(MetadataConstants.P_JOB_ID) + "/" + ResourceStore.CUBE_STATISTICS_ROOT + "/" + cubeId + "/" + segmentId + "/"; Path statisticsFile = new Path(statisticsDir, BatchConstants.CFG_STATISTICS_CUBOID_ESTIMATION_FILENAME); FileSystem fs = HadoopUtil.getWorkingFileSystem(); if (fs.exists(statisticsFile)) { FSDataInputStream is = fs.open(statisticsFile); //{color:red}未关闭流{color} ResourceStore.getStore(config).putBigResource(resKey, is, System.currentTimeMillis()); } CubeUpdate update = new CubeUpdate(currentInstanceCopy); update.setCuboids(distCube.getCuboids()); List<CubeSegment> toRemoveSegs = Lists.newArrayList(); 4. 研测验证: Path statisticsFile = new Path(statisticsDir, BatchConstants.CFG_STATISTICS_CUBOID_ESTIMATION_FILENAME); FileSystem fs = HadoopUtil.getWorkingFileSystem(); if (fs.exists(statisticsFile)) { try (FSDataInputStream is = fs.open(statisticsFile)) { // {color:red}关闭流{color} ResourceStore.getStore(config).putBigResource(resKey, is, System.currentTimeMillis()); } } 修改代码后,在研测环境进行多轮cube构建测试,CLOSE_WAIT 均无增加,验证解决。 -- This message was sent by Atlassian Jira (v8.20.10#820010)