YARN-1879. Marked Idempotent/AtMostOnce annotations to ApplicationMasterProtocol for RM fail over. Contributed by Tsuyoshi OZAWA

(cherry picked from commit c3de2412eb)
This commit is contained in:
Jian He 2014-10-17 16:35:13 -07:00
parent 5e239640f9
commit 78a57087bf
8 changed files with 178 additions and 138 deletions

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@ -334,6 +334,9 @@ Release 2.6.0 - UNRELEASED
YARN-2621. Simplify the output when the user doesn't have the access for YARN-2621. Simplify the output when the user doesn't have the access for
getDomain(s). (Zhijie Shen via jianhe) getDomain(s). (Zhijie Shen via jianhe)
YARN-1879. Marked Idempotent/AtMostOnce annotations to ApplicationMasterProtocol
for RM fail over. (Tsuyoshi OZAWA via jianhe)
OPTIMIZATIONS OPTIMIZATIONS
BUG FIXES BUG FIXES

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@ -23,6 +23,7 @@ import java.io.IOException;
import org.apache.hadoop.classification.InterfaceAudience.Public; import org.apache.hadoop.classification.InterfaceAudience.Public;
import org.apache.hadoop.classification.InterfaceStability.Stable; import org.apache.hadoop.classification.InterfaceStability.Stable;
import org.apache.hadoop.io.retry.AtMostOnce; import org.apache.hadoop.io.retry.AtMostOnce;
import org.apache.hadoop.io.retry.Idempotent;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest; import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse; import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest; import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest;
@ -80,6 +81,7 @@ public interface ApplicationMasterProtocol {
*/ */
@Public @Public
@Stable @Stable
@Idempotent
public RegisterApplicationMasterResponse registerApplicationMaster( public RegisterApplicationMasterResponse registerApplicationMaster(
RegisterApplicationMasterRequest request) RegisterApplicationMasterRequest request)
throws YarnException, IOException; throws YarnException, IOException;
@ -104,6 +106,7 @@ public interface ApplicationMasterProtocol {
*/ */
@Public @Public
@Stable @Stable
@AtMostOnce
public FinishApplicationMasterResponse finishApplicationMaster( public FinishApplicationMasterResponse finishApplicationMaster(
FinishApplicationMasterRequest request) FinishApplicationMasterRequest request)
throws YarnException, IOException; throws YarnException, IOException;

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@ -18,6 +18,14 @@
package org.apache.hadoop.yarn.client; package org.apache.hadoop.yarn.client;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.Map;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterResponse;
import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterRequest;
import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterResponse;
import org.apache.hadoop.yarn.api.records.ApplicationAccessType;
import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse; import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue; import static org.junit.Assert.assertTrue;
@ -122,6 +130,22 @@ import org.junit.After;
import org.junit.Before; import org.junit.Before;
/**
* Test Base for ResourceManager's Protocol on HA.
*
* Limited scope:
* For all the test cases, we only test whether the method will be re-entered
* when failover happens. Does not cover the entire logic of test.
*
* Test strategy:
* Create a separate failover thread with a trigger flag,
* override all APIs that are added trigger flag.
* When the APIs are called, we will set trigger flag as true to kick off
* the failover. So We can make sure the failover happens during process
* of the method. If this API is marked as @Idempotent or @AtMostOnce,
* the test cases will pass; otherwise, they will throw the exception.
*
*/
public abstract class ProtocolHATestBase extends ClientBaseWithFixes { public abstract class ProtocolHATestBase extends ClientBaseWithFixes {
protected static final HAServiceProtocol.StateChangeRequestInfo req = protected static final HAServiceProtocol.StateChangeRequestInfo req =
new HAServiceProtocol.StateChangeRequestInfo( new HAServiceProtocol.StateChangeRequestInfo(
@ -760,6 +784,43 @@ public abstract class ProtocolHATestBase extends ClientBaseWithFixes{
return createFakeAllocateResponse(); return createFakeAllocateResponse();
} }
@Override
public RegisterApplicationMasterResponse registerApplicationMaster(
RegisterApplicationMasterRequest request) throws YarnException,
IOException {
resetStartFailoverFlag(true);
// make sure failover has been triggered
Assert.assertTrue(waittingForFailOver());
return createFakeRegisterApplicationMasterResponse();
}
@Override
public FinishApplicationMasterResponse finishApplicationMaster(
FinishApplicationMasterRequest request) throws YarnException,
IOException {
resetStartFailoverFlag(true);
// make sure failover has been triggered
Assert.assertTrue(waittingForFailOver());
return createFakeFinishApplicationMasterResponse();
}
}
public RegisterApplicationMasterResponse
createFakeRegisterApplicationMasterResponse() {
Resource minCapability = Resource.newInstance(2048, 2);
Resource maxCapability = Resource.newInstance(4096, 4);
Map<ApplicationAccessType, String> acls =
new HashMap<ApplicationAccessType, String>();
acls.put(ApplicationAccessType.MODIFY_APP, "*");
ByteBuffer key = ByteBuffer.wrap("fake_key".getBytes());
return RegisterApplicationMasterResponse.newInstance(minCapability,
maxCapability, acls, key, new ArrayList<Container>(), "root",
new ArrayList<NMToken>());
}
public FinishApplicationMasterResponse
createFakeFinishApplicationMasterResponse() {
return FinishApplicationMasterResponse.newInstance(true);
} }
public AllocateResponse createFakeAllocateResponse() { public AllocateResponse createFakeAllocateResponse() {
@ -770,4 +831,5 @@ public abstract class ProtocolHATestBase extends ClientBaseWithFixes{
null, new ArrayList<NMToken>()); null, new ArrayList<NMToken>());
} }
} }
} }

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@ -1,92 +0,0 @@
/**
* 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.client;
import java.io.IOException;
import java.util.ArrayList;
import org.junit.Assert;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.ipc.RPC;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.yarn.api.ApplicationMasterProtocol;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse;
import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
import org.apache.hadoop.yarn.api.records.ContainerId;
import org.apache.hadoop.yarn.api.records.ResourceBlacklistRequest;
import org.apache.hadoop.yarn.api.records.ResourceRequest;
import org.apache.hadoop.yarn.exceptions.YarnException;
import org.apache.hadoop.yarn.security.AMRMTokenIdentifier;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttempt;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
public class TestApplicationMasterServiceOnHA extends ProtocolHATestBase{
private ApplicationMasterProtocol amClient;
private ApplicationAttemptId attemptId ;
RMAppAttempt appAttempt;
@Before
public void initiate() throws Exception {
startHACluster(0, false, false, true);
attemptId = this.cluster.createFakeApplicationAttemptId();
amClient = ClientRMProxy
.createRMProxy(this.conf, ApplicationMasterProtocol.class);
Token<AMRMTokenIdentifier> appToken =
this.cluster.getResourceManager().getRMContext()
.getAMRMTokenSecretManager().createAndGetAMRMToken(attemptId);
appToken.setService(ClientRMProxy.getAMRMTokenService(conf));
UserGroupInformation.setLoginUser(UserGroupInformation
.createRemoteUser(UserGroupInformation.getCurrentUser()
.getUserName()));
UserGroupInformation.getCurrentUser().addToken(appToken);
syncToken(appToken);
}
@After
public void shutDown() {
if(this.amClient != null) {
RPC.stopProxy(this.amClient);
}
}
@Test(timeout = 15000)
public void testAllocateOnHA() throws YarnException, IOException {
AllocateRequest request = AllocateRequest.newInstance(0, 50f,
new ArrayList<ResourceRequest>(),
new ArrayList<ContainerId>(),
ResourceBlacklistRequest.newInstance(new ArrayList<String>(),
new ArrayList<String>()));
AllocateResponse response = amClient.allocate(request);
Assert.assertEquals(response, this.cluster.createFakeAllocateResponse());
}
private void syncToken(Token<AMRMTokenIdentifier> token) throws IOException {
for (int i = 0; i < this.cluster.getNumOfResourceManager(); i++) {
this.cluster.getResourceManager(i).getRMContext()
.getAMRMTokenSecretManager().addPersistedPassword(token);
}
}
}

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@ -343,6 +343,15 @@ public class ApplicationMasterService extends AbstractService implements
authorizeRequest().getApplicationAttemptId(); authorizeRequest().getApplicationAttemptId();
ApplicationId appId = applicationAttemptId.getApplicationId(); ApplicationId appId = applicationAttemptId.getApplicationId();
RMApp rmApp =
rmContext.getRMApps().get(applicationAttemptId.getApplicationId());
// checking whether the app exits in RMStateStore at first not to throw
// ApplicationDoesNotExistInCacheException before and after
// RM work-preserving restart.
if (rmApp.isAppFinalStateStored()) {
return FinishApplicationMasterResponse.newInstance(true);
}
AllocateResponseLock lock = responseMap.get(applicationAttemptId); AllocateResponseLock lock = responseMap.get(applicationAttemptId);
if (lock == null) { if (lock == null) {
throwApplicationDoesNotExistInCacheException(applicationAttemptId); throwApplicationDoesNotExistInCacheException(applicationAttemptId);
@ -366,13 +375,6 @@ public class ApplicationMasterService extends AbstractService implements
this.amLivelinessMonitor.receivedPing(applicationAttemptId); this.amLivelinessMonitor.receivedPing(applicationAttemptId);
RMApp rmApp =
rmContext.getRMApps().get(appId);
if (rmApp.isAppFinalStateStored()) {
return FinishApplicationMasterResponse.newInstance(true);
}
rmContext.getDispatcher().getEventHandler().handle( rmContext.getDispatcher().getEventHandler().handle(
new RMAppAttemptUnregistrationEvent(applicationAttemptId, request new RMAppAttemptUnregistrationEvent(applicationAttemptId, request
.getTrackingUrl(), request.getFinalApplicationStatus(), request .getTrackingUrl(), request.getFinalApplicationStatus(), request

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@ -30,6 +30,7 @@ import org.apache.hadoop.yarn.api.ApplicationMasterProtocol;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest; import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse; import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest; import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterResponse;
import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterRequest; import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterRequest;
import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterResponse; import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterResponse;
import org.apache.hadoop.yarn.api.records.ApplicationAttemptId; import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
@ -51,6 +52,7 @@ public class MockAM {
private final ApplicationAttemptId attemptId; private final ApplicationAttemptId attemptId;
private RMContext context; private RMContext context;
private ApplicationMasterProtocol amRMProtocol; private ApplicationMasterProtocol amRMProtocol;
private UserGroupInformation ugi;
private final List<ResourceRequest> requests = new ArrayList<ResourceRequest>(); private final List<ResourceRequest> requests = new ArrayList<ResourceRequest>();
private final List<ContainerId> releases = new ArrayList<ContainerId>(); private final List<ContainerId> releases = new ArrayList<ContainerId>();
@ -101,15 +103,18 @@ public class MockAM {
req.setHost(""); req.setHost("");
req.setRpcPort(1); req.setRpcPort(1);
req.setTrackingUrl(""); req.setTrackingUrl("");
UserGroupInformation ugi = if (ugi == null) {
UserGroupInformation.createRemoteUser(attemptId.toString()); ugi = UserGroupInformation.createRemoteUser(
attemptId.toString());
Token<AMRMTokenIdentifier> token = Token<AMRMTokenIdentifier> token =
context.getRMApps().get(attemptId.getApplicationId()) context.getRMApps().get(attemptId.getApplicationId())
.getRMAppAttempt(attemptId).getAMRMToken(); .getRMAppAttempt(attemptId).getAMRMToken();
ugi.addTokenIdentifier(token.decodeIdentifier()); ugi.addTokenIdentifier(token.decodeIdentifier());
}
try { try {
return ugi return ugi
.doAs(new PrivilegedExceptionAction<RegisterApplicationMasterResponse>() { .doAs(
new PrivilegedExceptionAction<RegisterApplicationMasterResponse>() {
@Override @Override
public RegisterApplicationMasterResponse run() throws Exception { public RegisterApplicationMasterResponse run() throws Exception {
return amRMProtocol.registerApplicationMaster(req); return amRMProtocol.registerApplicationMaster(req);
@ -245,10 +250,15 @@ public class MockAM {
public void unregisterAppAttempt() throws Exception { public void unregisterAppAttempt() throws Exception {
waitForState(RMAppAttemptState.RUNNING); waitForState(RMAppAttemptState.RUNNING);
unregisterAppAttempt(true);
}
public void unregisterAppAttempt(boolean waitForStateRunning)
throws Exception {
final FinishApplicationMasterRequest req = final FinishApplicationMasterRequest req =
FinishApplicationMasterRequest.newInstance( FinishApplicationMasterRequest.newInstance(
FinalApplicationStatus.SUCCEEDED, "", ""); FinalApplicationStatus.SUCCEEDED, "", "");
unregisterAppAttempt(req,true); unregisterAppAttempt(req, waitForStateRunning);
} }
public void unregisterAppAttempt(final FinishApplicationMasterRequest req, public void unregisterAppAttempt(final FinishApplicationMasterRequest req,
@ -256,12 +266,15 @@ public class MockAM {
if (waitForStateRunning) { if (waitForStateRunning) {
waitForState(RMAppAttemptState.RUNNING); waitForState(RMAppAttemptState.RUNNING);
} }
UserGroupInformation ugi = if (ugi == null) {
UserGroupInformation.createRemoteUser(attemptId.toString()); ugi = UserGroupInformation.createRemoteUser(attemptId.toString());
Token<AMRMTokenIdentifier> token = Token<AMRMTokenIdentifier> token =
context.getRMApps().get(attemptId.getApplicationId()) context.getRMApps()
.get(attemptId.getApplicationId())
.getRMAppAttempt(attemptId).getAMRMToken(); .getRMAppAttempt(attemptId).getAMRMToken();
ugi.addTokenIdentifier(token.decodeIdentifier()); ugi.addTokenIdentifier(token.decodeIdentifier());
}
try {
ugi.doAs(new PrivilegedExceptionAction<Object>() { ugi.doAs(new PrivilegedExceptionAction<Object>() {
@Override @Override
public Object run() throws Exception { public Object run() throws Exception {
@ -269,6 +282,9 @@ public class MockAM {
return null; return null;
} }
}); });
} catch (UndeclaredThrowableException e) {
throw (Exception) e.getCause();
}
} }
public ApplicationAttemptId getApplicationAttemptId() { public ApplicationAttemptId getApplicationAttemptId() {

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@ -23,9 +23,7 @@ import org.apache.hadoop.yarn.proto.YarnServiceProtos.SchedulerResourceTypes;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler; import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration; import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler; import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler;
import org.apache.hadoop.yarn.util.resource.DefaultResourceCalculator;
import org.apache.hadoop.yarn.util.resource.DominantResourceCalculator; import org.apache.hadoop.yarn.util.resource.DominantResourceCalculator;
import org.junit.Assert;
import org.apache.commons.logging.Log; import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory; import org.apache.commons.logging.LogFactory;
@ -42,15 +40,19 @@ import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMApp;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.*; import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.*;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ResourceScheduler; import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ResourceScheduler;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fifo.FifoScheduler; import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fifo.FifoScheduler;
import org.apache.hadoop.yarn.server.utils.BuilderUtils; import org.apache.hadoop.yarn.server.utils.BuilderUtils;
import org.junit.BeforeClass; import org.junit.BeforeClass;
import org.junit.Test; import org.junit.Test;
import org.junit.Assert;
import java.util.*; import java.util.ArrayList;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import static java.lang.Thread.sleep; import static java.lang.Thread.sleep;
import static org.mockito.Matchers.any;
public class TestApplicationMasterService { public class TestApplicationMasterService {
private static final Log LOG = LogFactory.getLog(TestFifoScheduler.class); private static final Log LOG = LogFactory.getLog(TestFifoScheduler.class);
@ -240,25 +242,23 @@ public class TestApplicationMasterService {
FinishApplicationMasterRequest req = FinishApplicationMasterRequest req =
FinishApplicationMasterRequest.newInstance( FinishApplicationMasterRequest.newInstance(
FinalApplicationStatus.FAILED, "", ""); FinalApplicationStatus.FAILED, "", "");
Throwable cause = null;
try { try {
am1.unregisterAppAttempt(req, false); am1.unregisterAppAttempt(req, false);
Assert.fail("ApplicationMasterNotRegisteredException should be thrown");
} catch (ApplicationMasterNotRegisteredException e) {
Assert.assertNotNull(e);
Assert.assertNotNull(e.getMessage());
Assert.assertTrue(e.getMessage().contains(
"Application Master is trying to unregister before registering for:"
));
} catch (Exception e) { } catch (Exception e) {
cause = e.getCause(); Assert.fail("ApplicationMasterNotRegisteredException should be thrown");
} }
Assert.assertNotNull(cause);
Assert
.assertTrue(cause instanceof ApplicationMasterNotRegisteredException);
Assert.assertNotNull(cause.getMessage());
Assert
.assertTrue(cause
.getMessage()
.contains(
"Application Master is trying to unregister before registering for:"));
am1.registerAppAttempt(); am1.registerAppAttempt();
am1.unregisterAppAttempt(req, false); am1.unregisterAppAttempt(req, false);
am1.waitForState(RMAppAttemptState.FINISHING);
} finally { } finally {
if (rm != null) { if (rm != null) {
rm.stop(); rm.stop();

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@ -18,6 +18,8 @@
package org.apache.hadoop.yarn.server.resourcemanager; package org.apache.hadoop.yarn.server.resourcemanager;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.yarn.security.AMRMTokenIdentifier;
import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse; import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull; import static org.junit.Assert.assertNull;
@ -668,6 +670,9 @@ public class TestWorkPreservingRMRestart {
// create app and launch the AM // create app and launch the AM
RMApp app0 = rm1.submitApp(200); RMApp app0 = rm1.submitApp(200);
MockAM am0 = MockRM.launchAM(app0, rm1, nm1); MockAM am0 = MockRM.launchAM(app0, rm1, nm1);
// Issuing registerAppAttempt() before and after RM restart to confirm
// registerApplicationMaster() is idempotent.
am0.registerAppAttempt();
// start new RM // start new RM
rm2 = new MockRM(conf, memStore); rm2 = new MockRM(conf, memStore);
@ -676,6 +681,7 @@ public class TestWorkPreservingRMRestart {
rm2.waitForState(am0.getApplicationAttemptId(), RMAppAttemptState.LAUNCHED); rm2.waitForState(am0.getApplicationAttemptId(), RMAppAttemptState.LAUNCHED);
am0.setAMRMProtocol(rm2.getApplicationMasterService(), rm2.getRMContext()); am0.setAMRMProtocol(rm2.getApplicationMasterService(), rm2.getRMContext());
// retry registerApplicationMaster() after RM restart.
am0.registerAppAttempt(true); am0.registerAppAttempt(true);
rm2.waitForState(app0.getApplicationId(), RMAppState.RUNNING); rm2.waitForState(app0.getApplicationId(), RMAppState.RUNNING);
@ -897,4 +903,44 @@ public class TestWorkPreservingRMRestart {
Thread.sleep(500); Thread.sleep(500);
} }
} }
/**
* Testing to confirm that retried finishApplicationMaster() doesn't throw
* InvalidApplicationMasterRequest before and after RM restart.
*/
@Test (timeout = 20000)
public void testRetriedFinishApplicationMasterRequest()
throws Exception {
conf.setInt(YarnConfiguration.RM_AM_MAX_ATTEMPTS, 1);
MemoryRMStateStore memStore = new MemoryRMStateStore();
memStore.init(conf);
// start RM
rm1 = new MockRM(conf, memStore);
rm1.start();
MockNM nm1 =
new MockNM("127.0.0.1:1234", 15120, rm1.getResourceTrackerService());
nm1.registerNode();
// create app and launch the AM
RMApp app0 = rm1.submitApp(200);
MockAM am0 = MockRM.launchAM(app0, rm1, nm1);
am0.registerAppAttempt();
// Emulating following a scenario:
// RM1 saves the app in RMStateStore and then crashes,
// FinishApplicationMasterResponse#isRegistered still return false,
// so AM still retry the 2nd RM
MockRM.finishAMAndVerifyAppState(app0, rm1, nm1, am0);
// start new RM
rm2 = new MockRM(conf, memStore);
rm2.start();
am0.setAMRMProtocol(rm2.getApplicationMasterService(), rm2.getRMContext());
am0.unregisterAppAttempt(false);
}
} }