Hadoop Yarn 创建Application
Posted 李孟lm
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文章目录
一.简介
创建Application是由client向ResourceManager发起申请，client与RM之间的通信依靠Hadoop RPC，通信协议是ApplicationClientProtocol，所谓通信协议实际上就是一个接口，接口中说明了server/client具备哪些操作函数。
二.源码
2.1 Client
public boolean run() throws IOException, YarnException {
LOG.info("Running Client");
yarnClient.start();
YarnClusterMetrics clusterMetrics = yarnClient.getYarnClusterMetrics();
LOG.info("Got Cluster metric info from ASM"
+ ", numNodeManagers=" + clusterMetrics.getNumNodeManagers());
List<NodeReport> clusterNodeReports = yarnClient.getNodeReports(
NodeState.RUNNING);
LOG.info("Got Cluster node info from ASM");
for (NodeReport node : clusterNodeReports) {
LOG.info("Got node report from ASM for"
+ ", nodeId=" + node.getNodeId()
+ ", nodeAddress" + node.getHttpAddress()
+ ", nodeRackName" + node.getRackName()
+ ", nodeNumContainers" + node.getNumContainers());
}
QueueInfo queueInfo = yarnClient.getQueueInfo(this.amQueue);
LOG.info("Queue info"
+ ", queueName=" + queueInfo.getQueueName()
+ ", queueCurrentCapacity=" + queueInfo.getCurrentCapacity()
+ ", queueMaxCapacity=" + queueInfo.getMaximumCapacity()
+ ", queueApplicationCount=" + queueInfo.getApplications().size()
+ ", queueChildQueueCount=" + queueInfo.getChildQueues().size());
List<QueueUserACLInfo> listAclInfo = yarnClient.getQueueAclsInfo();
for (QueueUserACLInfo aclInfo : listAclInfo) {
for (QueueACL userAcl : aclInfo.getUserAcls()) {
LOG.info("User ACL Info for Queue"
+ ", queueName=" + aclInfo.getQueueName()
+ ", userAcl=" + userAcl.name());
}
}
if (domainId != null && domainId.length() > 0 && toCreateDomain) {
prepareTimelineDomain();
}
// Get a new application id
// 创建application
YarnClientApplication app = yarnClient.createApplication();
GetNewApplicationResponse appResponse = app.getNewApplicationResponse();
// TODO get min/max resource capabilities from RM and change memory ask if needed
// If we do not have min/max, we may not be able to correctly request
// the required resources from the RM for the app master
// Memory ask has to be a multiple of min and less than max.
// Dump out information about cluster capability as seen by the resource manager
int maxMem = appResponse.getMaximumResourceCapability().getMemory();
LOG.info("Max mem capabililty of resources in this cluster " + maxMem);
// A resource ask cannot exceed the max.
if (amMemory > maxMem) {
LOG.info("AM memory specified above max threshold of cluster. Using max value."
+ ", specified=" + amMemory
+ ", max=" + maxMem);
amMemory = maxMem;
}
int maxVCores = appResponse.getMaximumResourceCapability().getVirtualCores();
LOG.info("Max virtual cores capabililty of resources in this cluster " + maxVCores);
if (amVCores > maxVCores) {
LOG.info("AM virtual cores specified above max threshold of cluster. "
+ "Using max value." + ", specified=" + amVCores
+ ", max=" + maxVCores);
amVCores = maxVCores;
}
// set the application name
ApplicationSubmissionContext appContext = app.getApplicationSubmissionContext();
ApplicationId appId = appContext.getApplicationId();
appContext.setKeepContainersAcrossApplicationAttempts(keepContainers);
appContext.setApplicationName(appName);
if (attemptFailuresValidityInterval >= 0) {
appContext
.setAttemptFailuresValidityInterval(attemptFailuresValidityInterval);
}
// set local resources for the application master
// local files or archives as needed
// In this scenario, the jar file for the application master is part of the local resources
Map<String, LocalResource> localResources = new HashMap<String, LocalResource>();
LOG.info("Copy App Master jar from local filesystem and add to local environment");
// Copy the application master jar to the filesystem
// Create a local resource to point to the destination jar path
FileSystem fs = FileSystem.get(conf);
addToLocalResources(fs, appMasterJar, appMasterJarPath, appId.toString(),
localResources, null);
// Set the log4j properties if needed
if (!log4jPropFile.isEmpty()) {
addToLocalResources(fs, log4jPropFile, log4jPath, appId.toString(),
localResources, null);
}
// The shell script has to be made available on the final container(s)
// where it will be executed.
// To do this, we need to first copy into the filesystem that is visible
// to the yarn framework.
// We do not need to set this as a local resource for the application
// master as the application master does not need it.
String hdfsShellScriptLocation = "";
long hdfsShellScriptLen = 0;
long hdfsShellScriptTimestamp = 0;
if (!shellScriptPath.isEmpty()) {
Path shellSrc = new Path(shellScriptPath);
String shellPathSuffix =
appName + "/" + appId.toString() + "/" + SCRIPT_PATH;
Path shellDst =
new Path(fs.getHomeDirectory(), shellPathSuffix);
fs.copyFromLocalFile(false, true, shellSrc, shellDst);
hdfsShellScriptLocation = shellDst.toUri().toString();
FileStatus shellFileStatus = fs.getFileStatus(shellDst);
hdfsShellScriptLen = shellFileStatus.getLen();
hdfsShellScriptTimestamp = shellFileStatus.getModificationTime();
}
if (!shellCommand.isEmpty()) {
addToLocalResources(fs, null, shellCommandPath, appId.toString(),
localResources, shellCommand);
}
if (shellArgs.length > 0) {
addToLocalResources(fs, null, shellArgsPath, appId.toString(),
localResources, StringUtils.join(shellArgs, " "));
}
// Set the necessary security tokens as needed
//amContainer.setContainerTokens(containerToken);
// Set the env variables to be setup in the env where the application master will be run
LOG.info("Set the environment for the application master");
Map<String, String> env = new HashMap<String, String>();
// put location of shell script into env
// using the env info, the application master will create the correct local resource for the
// eventual containers that will be launched to execute the shell scripts
env.put(DSConstants.DISTRIBUTEDSHELLSCRIPTLOCATION, hdfsShellScriptLocation);
env.put(DSConstants.DISTRIBUTEDSHELLSCRIPTTIMESTAMP, Long.toString(hdfsShellScriptTimestamp));
env.put(DSConstants.DISTRIBUTEDSHELLSCRIPTLEN, Long.toString(hdfsShellScriptLen));
if (domainId != null && domainId.length() > 0) {
env.put(DSConstants.DISTRIBUTEDSHELLTIMELINEDOMAIN, domainId);
}
// Add AppMaster.jar location to classpath
// At some point we should not be required to add
// the hadoop specific classpaths to the env.
// It should be provided out of the box.
// For now setting all required classpaths including
// the classpath to "." for the application jar
StringBuilder classPathEnv = new StringBuilder(Environment.CLASSPATH.$$())
.append(ApplicationConstants.CLASS_PATH_SEPARATOR).append("./*");
for (String c : conf.getStrings(
YarnConfiguration.YARN_APPLICATION_CLASSPATH,
YarnConfiguration.DEFAULT_YARN_CROSS_PLATFORM_APPLICATION_CLASSPATH)) {
classPathEnv.append(ApplicationConstants.CLASS_PATH_SEPARATOR);
classPathEnv.append(c.trim());
}
classPathEnv.append(ApplicationConstants.CLASS_PATH_SEPARATOR).append(
"./log4j.properties");
// add the runtime classpath needed for tests to work
if (conf.getBoolean(YarnConfiguration.IS_MINI_YARN_CLUSTER, false)) {
classPathEnv.append(':');
classPathEnv.append(System.getProperty("java.class.path"));
}
env.put("CLASSPATH", classPathEnv.toString());
// Set the necessary command to execute the application master
Vector<CharSequence> vargs = new Vector<CharSequence>(30);
// Set java executable command
LOG.info("Setting up app master command");
vargs.add(Environment.JAVA_HOME.$$() + "/bin/java");
// Set Xmx based on am memory size
vargs.add("-Xmx" + amMemory + "m");
// Set class name
vargs.add(appMasterMainClass);
// Set params for Application Master
vargs.add("--container_memory " + String.valueOf(containerMemory));
vargs.add("--container_vcores " + String.valueOf(containerVirtualCores));
vargs.add("--num_containers " + String.valueOf(numContainers));
if (null != nodeLabelExpression) {
appContext.setNodeLabelExpression(nodeLabelExpression);
}
vargs.add("--priority " + String.valueOf(shellCmdPriority));
for (Map.Entry<String, String> entry : shellEnv.entrySet()) {
vargs.add("--shell_env " + entry.getKey() + "=" + entry.getValue());
}
if (debugFlag) {
vargs.add("--debug");
}
vargs.add("1>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/AppMaster.stdout");
vargs.add("2>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/AppMaster.stderr");
// Get final commmand
StringBuilder command = new StringBuilder();
for (CharSequence str : vargs) {
command.append(str).append(" ");
}
LOG.info("Completed setting up app master command " + command.toString());
List<String> commands = new ArrayList<String>();
commands.add(command.toString());
// Set up the container launch context for the application master
ContainerLaunchContext amContainer = ContainerLaunchContext.newInstance(
localResources, env, commands, null, null, null);
// Set up resource type requirements
// For now, both memory and vcores are supported, so we set memory and
// vcores requirements
Resource capability = Resource.newInstance(amMemory, amVCores);
appContext.setResource(capability);
// Service data is a binary blob that can be passed to the application
// Not needed in this scenario
// amContainer.setServiceData(serviceData);
// Setup security tokens
if (UserGroupInformation.isSecurityEnabled()) {
// Note: Credentials class is marked as LimitedPrivate for HDFS and MapReduce
Credentials credentials = new Credentials();
String tokenRenewer = conf.get(YarnConfiguration.RM_PRINCIPAL);
if (tokenRenewer == null || tokenRenewer.length() == 0) {
throw new IOException(
"Can't get Master Kerberos principal for the RM to use as renewer");
}
// For now, only getting tokens for the default file-system.
final Token<?> tokens[] =
fs.addDelegationTokens(tokenRenewer, credentials);
if (tokens != null) {
for (Token<?> token : tokens) {
LOG.info("Got dt for " + fs.getUri() + "; " + token);
}
}
DataOutputBuffer dob = new DataOutputBuffer();
credentials.writeTokenStorageToStream(dob);
ByteBuffer fsTokens = ByteBuffer.wrap(dob.getData(), 0, dob.getLength());
amContainer.setTokens(fsTokens);
}
appContext.setAMContainerSpec(amContainer);
// Set the priority for the application master
// TODO - what is the range for priority? how to decide?
Priority pri = Priority.newInstance(amPriority);
appContext.setPriority(pri);
// Set the queue to which this application is to be submitted in the RM
appContext.setQueue(amQueue);
// Submit the application to the applications manager
// SubmitApplicationResponse submitResp = applicationsManager.submitApplication(appRequest);
// Ignore the response as either a valid response object is returned on success
// or an exception thrown to denote some form of a failure
LOG.info("Submitting application to ASM");
//
yarnClient.submitApplication(appContext);
// TODO
// Try submitting the same request again
// app submission failure?
// Monitor the application
return monitorApplication(appId);
}
2.1.1 Client -> YarnClientApplication app = yarnClient.createApplication();
YarnClientImpl
@Override
public YarnClientApplication createApplication()
throws YarnException, IOException {
ApplicationSubmissionContext context = Records.newRecord
(ApplicationSubmissionContext.class);
GetNewApplicationResponse newApp = getNewApplication();
ApplicationId appId = newApp.getApplicationId();
context.setApplicationId(appId);
return new YarnClientApplication(newApp, context);
}
private GetNewApplicationResponse getNewApplication()
throws YarnException, IOException {
GetNewApplicationRequest request =
Records.newRecord(GetNewApplicationRequest.class);
return rmClient.getNewApplication(request);
}
rmClient是一个RPC client，那么getNewApplication要去RPC server才能看到是怎么实现的, 上面也说到了server端的实现在ClientRMService中，那就去里面找呗。
ClientRMService
ApplicationId getNewApplicationId() {
ApplicationId applicationId = org.apache.hadoop.yarn.server.utils.BuilderUtils
.newApplicationId(recordFactory, ResourceManager.getClusterTimeStamp(),
applicationCounter.incrementAndGet());
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