Hean-Chhinling commented on code in PR #8123: URL: https://github.com/apache/hadoop/pull/8123#discussion_r2873067277
########## hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/webapp/DiagnosticJStackService.java: ########## @@ -0,0 +1,139 @@ +/** * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.hadoop.yarn.server.nodemanager.webapp; + + +import org.apache.hadoop.classification.VisibleForTesting; +import org.apache.hadoop.util.Shell; +import org.apache.hadoop.yarn.api.records.ApplicationId; +import org.apache.hadoop.yarn.api.records.ContainerId; +import org.apache.hadoop.yarn.server.nodemanager.Context; +import org.apache.hadoop.yarn.server.nodemanager.containermanager.application.Application; +import org.apache.hadoop.yarn.server.nodemanager.containermanager.container.Container; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.io.IOException; +import java.util.ArrayList; +import java.util.List; +import java.util.Map; +import java.util.Optional; +import java.util.Arrays; + +public class DiagnosticJStackService { + + private final Context context; + private static final Logger LOG = LoggerFactory + .getLogger(DiagnosticJStackService.class); + + public DiagnosticJStackService(Context context) { + this.context = context; + } + + public String collectNodeThreadDump(int numberOfJStack) + throws IOException { + checkShellNotWindows(); + + long nodeManagerPid = ProcessHandle.current().pid(); + + return runJStack(nodeManagerPid, numberOfJStack); + } + + public String collectApplicationThreadDump(String appId, int numberOfJStack) + throws IOException { + if(!appId.matches("application_\\d{13}_\\d{4}")) { + throw new RuntimeException("Invalid application id: " + appId); + } + checkShellNotWindows(); + + List<Long> applicationPids = getApplicationPids(appId); + + return runJStack(applicationPids, numberOfJStack); + } + + private void checkShellNotWindows() { + if (Shell.WINDOWS) { + throw new UnsupportedOperationException("Not implemented for Windows."); + } + } + + @VisibleForTesting + List<Long> getApplicationPids(String appId){ + List<Long> pids = new ArrayList<>(); + + ApplicationId appIdObj = ApplicationId.fromString(appId); + Application app = context.getApplications().get(appIdObj); + if (app != null) { + Map<ContainerId, Container> containers = app.getContainers(); + for (ContainerId containerId : containers.keySet()){ + long pidForContainerId = Long.parseLong(context.getContainerExecutor().getProcessId(containerId)); + + ProcessHandle.of(pidForContainerId).ifPresent(parentProcess -> + parentProcess.descendants() + .filter(childProcess -> + childProcess.info().command().orElse("").contains("java")) + .map(ProcessHandle::pid) + .forEach(pids::add) + ); + + } + } + + return pids; + + } + + private String runJStack(List<Long> pids, int numJStacks) throws IOException { + StringBuilder result = new StringBuilder(); + + for(Long pid : pids){ + result.append(runJStack(pid, numJStacks)); + } + + return result.toString(); + } + + private String runJStack(long pid, int numJStacks) throws IOException { + Optional<ProcessHandle> processHandle = ProcessHandle.of(pid); + + if (processHandle.isEmpty()){ + throw new IOException("Process with PID " + pid + " is no longer exists"); + } + + String processOwner = processHandle.get().info().user().orElse("root"); + String[] jstackCommand = {"sudo", "-u", processOwner, "jstack", String.valueOf(pid)}; Review Comment: Thank you for the suggestion, Bence. You are right! Somehow NM could personalise running the application as another user. That means it also possible to run jstack as another user using code from NM. I am looking into the change_user method. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
