烂sql导致clickhouse集群memory_tracking直线飙升触发熔断
版本version 19.17.4.11 clickhouse 集群,主要存日志数据与监控数据。架构为4台主机12个实例数,数据为单副本。近日,该clickhouse集群有一台物理机的硬件(电池)损坏,损坏的硬件完成更换后,就有人反馈数据查询异常,报DB::Exception: Memory limit (total)&nbs
hadoop之 exceeds the limit of concurrent xcievers处理
dfs.datanode.max.transfer.threads: 默认 4096 < 2.0之前该参数为dfs.datanode.max.xcievers >解释:Specifies the maximum number of threads to use for transferring data in and out of the DN.表示datanode上负责进行文件操作的线程数。如果需要处理的文件过多,而这个参数设置得过低就会有一部分文件处理不...
hadoop之 node manager起不来, 执行mapreduce 程序hang住
现象: node manager起不来, 执行mapreduce 程序hang住namenode 进程状态查询[root@hadp-master sbin]# jps8608 ResourceManager8257 NameNode9268 Jps8453 SecondaryNameNodedatanode 进程状态查询 , 发现 nodemanager 没有起来[root@hadp-node1 hadoop]# jps4179 DataNode4940 Jpsnamenode 单独起 no...
hadoop之 安全模式及SafeModeException
问题: hadoop启动的时候报错HTTP ERROR 500 Problem accessing /nn_browsedfscontent.jsp. Reason: Cannot issue delegation token. Name node is in safe mode. The reported blocks 0 needs additional 10 blocks to reach the threshold 0.9990 of total blocks 10. Safe mode will be ...