Hive 执行查询语句报错，由于内存空间不足导致

org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.server.namenode.SafeModeException): Cannot create directory /tmp/hive/root/5a62374a-9509-4d20-befb-de0e00c0e7ad/hive_2019-06-14_11-12-24_067_6655769013562582754-1/-mr-10016. Name node is in safe mode.
Resources are low on NN. Please add or free up more resources then turn off safe mode manually. NOTE:  If you turn off safe mode before adding resources, the NN will immediately return to safe mode. Use "hdfs dfsadmin -safemode leave" to turn safe mode off.
        at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkNameNodeSafeMode(FSNamesystem.java:1366)
        at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInt(FSNamesystem.java:4258)
        at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirs(FSNamesystem.java:4233)
        at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.mkdirs(NameNodeRpcServer.java:853)
        at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.mkdirs(ClientNamenodeProtocolServerSideTranslatorPB.java:600)
        at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
        at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619)
        at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:975)
        at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2040)
        at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2036)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:422)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692)
        at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2034)

        at org.apache.hadoop.ipc.Client.call(Client.java:1470)
        at org.apache.hadoop.ipc.Client.call(Client.java:1401)
        at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:232)
        at com.sun.proxy.$Proxy11.mkdirs(Unknown Source)
        at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.mkdirs(ClientNamenodeProtocolTranslatorPB.java:539)
        at sun.reflect.GeneratedMethodAccessor15.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:187)
        at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
        at com.sun.proxy.$Proxy12.mkdirs(Unknown Source)
        at org.apache.hadoop.hdfs.DFSClient.primitiveMkdir(DFSClient.java:2742)
        at org.apache.hadoop.hdfs.DFSClient.mkdirs(DFSClient.java:2713)
        at org.apache.hadoop.hdfs.DistributedFileSystem$17.doCall(DistributedFileSystem.java:870)
        at org.apache.hadoop.hdfs.DistributedFileSystem$17.doCall(DistributedFileSystem.java:866)
        at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
        at org.apache.hadoop.hdfs.DistributedFileSystem.mkdirsInternal(DistributedFileSystem.java:866)
        at org.apache.hadoop.hdfs.DistributedFileSystem.mkdirs(DistributedFileSystem.java:859)
        at org.apache.hadoop.fs.FileSystem.mkdirs(FileSystem.java:1819)
        at org.apache.hadoop.hive.ql.exec.mr.ExecDriver.execute(ExecDriver.java:227)
        at org.apache.hadoop.hive.ql.exec.mr.MapRedTask.execute(MapRedTask.java:137)
        at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:160)
        at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:88)
        at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:1676)
        at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:1435)
        at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1218)
        at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1082)
        at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1072)
        at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:213)
        at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:165)
        at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:376)
        at org.apache.hadoop.hive.cli.CliDriver.executeDriver(CliDriver.java:736)
        at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:681)
        at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:621)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
        at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Error launching map-reduce job
FAILED: Execution Error, return code 5 from org.apache.hadoop.hive.ql.exec.mr.MapRedTask

　　提示说是因为远程问题，直接给出的提示即可。

NOTE:  If you turn off safe mode before adding resources, the NN will immediately return to safe mode. Use "hdfs dfsadmin -safemode leave" to turn safe mode off.

　　已经告诉我们，使用

hdfs dfsadmin -safemode leave

　　将安全模型关闭，但是关闭安全模式之后发现再次执行同样的语句还是得到同样的结果，查阅资料，是因为内存空间不足导致的。

# 使用 df -hl 查看空间使用情况
df -hl

# 使用 du -sh /* 查看哪些大文件占用了空间
du -sh /*

# 将对应的内存空间释放之后，问题就解决了。