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19 package org.apache.hadoop.hbase.master.handler;
20
21 import java.io.IOException;
22 import java.io.InterruptedIOException;
23 import java.util.ArrayList;
24 import java.util.HashSet;
25 import java.util.List;
26 import java.util.Map;
27 import java.util.NavigableMap;
28 import java.util.Set;
29 import java.util.concurrent.locks.Lock;
30
31 import org.apache.commons.logging.Log;
32 import org.apache.commons.logging.LogFactory;
33 import org.apache.hadoop.classification.InterfaceAudience;
34 import org.apache.hadoop.hbase.HConstants;
35 import org.apache.hadoop.hbase.HRegionInfo;
36 import org.apache.hadoop.hbase.Server;
37 import org.apache.hadoop.hbase.ServerName;
38 import org.apache.hadoop.hbase.catalog.CatalogTracker;
39 import org.apache.hadoop.hbase.catalog.MetaReader;
40 import org.apache.hadoop.hbase.client.Result;
41 import org.apache.hadoop.hbase.executor.EventHandler;
42 import org.apache.hadoop.hbase.executor.EventType;
43 import org.apache.hadoop.hbase.master.AssignmentManager;
44 import org.apache.hadoop.hbase.master.DeadServer;
45 import org.apache.hadoop.hbase.master.MasterServices;
46 import org.apache.hadoop.hbase.master.RegionState;
47 import org.apache.hadoop.hbase.master.RegionState.State;
48 import org.apache.hadoop.hbase.master.RegionStates;
49 import org.apache.hadoop.hbase.master.ServerManager;
50 import org.apache.hadoop.hbase.regionserver.wal.HLogSplitter;
51 import org.apache.hadoop.hbase.zookeeper.ZKAssign;
52 import org.apache.zookeeper.KeeperException;
53
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58
59 @InterfaceAudience.Private
60 public class ServerShutdownHandler extends EventHandler {
61 private static final Log LOG = LogFactory.getLog(ServerShutdownHandler.class);
62 protected final ServerName serverName;
63 protected final MasterServices services;
64 protected final DeadServer deadServers;
65 protected final boolean shouldSplitHlog;
66 protected final boolean distributedLogReplay;
67 protected final int regionAssignmentWaitTimeout;
68
69 public ServerShutdownHandler(final Server server, final MasterServices services,
70 final DeadServer deadServers, final ServerName serverName,
71 final boolean shouldSplitHlog) {
72 this(server, services, deadServers, serverName, EventType.M_SERVER_SHUTDOWN,
73 shouldSplitHlog);
74 }
75
76 ServerShutdownHandler(final Server server, final MasterServices services,
77 final DeadServer deadServers, final ServerName serverName, EventType type,
78 final boolean shouldSplitHlog) {
79 super(server, type);
80 this.serverName = serverName;
81 this.server = server;
82 this.services = services;
83 this.deadServers = deadServers;
84 if (!this.deadServers.isDeadServer(this.serverName)) {
85 LOG.warn(this.serverName + " is NOT in deadservers; it should be!");
86 }
87 this.shouldSplitHlog = shouldSplitHlog;
88 this.distributedLogReplay = HLogSplitter.isDistributedLogReplay(server.getConfiguration());
89 this.regionAssignmentWaitTimeout = server.getConfiguration().getInt(
90 HConstants.LOG_REPLAY_WAIT_REGION_TIMEOUT, 15000);
91 }
92
93 @Override
94 public String getInformativeName() {
95 if (serverName != null) {
96 return this.getClass().getSimpleName() + " for " + serverName;
97 } else {
98 return super.getInformativeName();
99 }
100 }
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104
105 boolean isCarryingMeta() {
106 return false;
107 }
108
109 @Override
110 public String toString() {
111 String name = "UnknownServerName";
112 if(server != null && server.getServerName() != null) {
113 name = server.getServerName().toString();
114 }
115 return getClass().getSimpleName() + "-" + name + "-" + getSeqid();
116 }
117
118 @Override
119 public void process() throws IOException {
120 boolean hasLogReplayWork = false;
121 final ServerName serverName = this.serverName;
122 try {
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145 AssignmentManager am = services.getAssignmentManager();
146 if (isCarryingMeta()
147 || !am.isFailoverCleanupDone()) {
148 this.services.getServerManager().processDeadServer(serverName, this.shouldSplitHlog);
149 return;
150 }
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167 NavigableMap<HRegionInfo, Result> hris = null;
168 while (!this.server.isStopped()) {
169 try {
170 this.server.getCatalogTracker().waitForMeta();
171 hris = MetaReader.getServerUserRegions(this.server.getCatalogTracker(),
172 this.serverName);
173 break;
174 } catch (InterruptedException e) {
175 Thread.currentThread().interrupt();
176 throw (InterruptedIOException)new InterruptedIOException().initCause(e);
177 } catch (IOException ioe) {
178 LOG.info("Received exception accessing hbase:meta during server shutdown of " +
179 serverName + ", retrying hbase:meta read", ioe);
180 }
181 }
182 if (this.server.isStopped()) {
183 throw new IOException("Server is stopped");
184 }
185
186 try {
187 if (this.shouldSplitHlog) {
188 LOG.info("Splitting logs for " + serverName + " before assignment.");
189 if (this.distributedLogReplay) {
190 LOG.info("Mark regions in recovery before assignment.");
191 Set<ServerName> serverNames = new HashSet<ServerName>();
192 serverNames.add(serverName);
193 this.services.getMasterFileSystem().prepareLogReplay(serverNames);
194 } else {
195 this.services.getMasterFileSystem().splitLog(serverName);
196 }
197 am.getRegionStates().logSplit(serverName);
198 } else {
199 LOG.info("Skipping log splitting for " + serverName);
200 }
201 } catch (IOException ioe) {
202 resubmit(serverName, ioe);
203 }
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209 List<HRegionInfo> regionsInTransition = am.processServerShutdown(serverName);
210 LOG.info("Reassigning " + ((hris == null)? 0: hris.size()) +
211 " region(s) that " + (serverName == null? "null": serverName) +
212 " was carrying (and " + regionsInTransition.size() +
213 " regions(s) that were opening on this server)");
214
215 List<HRegionInfo> toAssignRegions = new ArrayList<HRegionInfo>();
216 toAssignRegions.addAll(regionsInTransition);
217
218
219 if (hris != null) {
220 RegionStates regionStates = am.getRegionStates();
221 for (Map.Entry<HRegionInfo, Result> e: hris.entrySet()) {
222 HRegionInfo hri = e.getKey();
223 if (regionsInTransition.contains(hri)) {
224 continue;
225 }
226 String encodedName = hri.getEncodedName();
227 Lock lock = am.acquireRegionLock(encodedName);
228 try {
229 RegionState rit = regionStates.getRegionTransitionState(hri);
230 if (processDeadRegion(hri, e.getValue(), am, server.getCatalogTracker())) {
231 ServerName addressFromAM = regionStates.getRegionServerOfRegion(hri);
232 if (addressFromAM != null && !addressFromAM.equals(this.serverName)) {
233
234
235 LOG.info("Skip assigning region " + hri.getRegionNameAsString()
236 + " because it has been opened in " + addressFromAM.getServerName());
237 continue;
238 }
239 if (rit != null) {
240 if (rit.getServerName() != null && !rit.isOnServer(serverName)) {
241
242 LOG.info("Skip assigning region in transition on other server" + rit);
243 continue;
244 }
245 try{
246
247 LOG.info("Reassigning region with rs = " + rit + " and deleting zk node if exists");
248 ZKAssign.deleteNodeFailSilent(services.getZooKeeper(), hri);
249 regionStates.updateRegionState(hri, State.OFFLINE);
250 } catch (KeeperException ke) {
251 this.server.abort("Unexpected ZK exception deleting unassigned node " + hri, ke);
252 return;
253 }
254 } else if (regionStates.isRegionInState(
255 hri, State.SPLITTING_NEW, State.MERGING_NEW)) {
256 regionStates.regionOffline(hri);
257 }
258 toAssignRegions.add(hri);
259 } else if (rit != null) {
260 if (rit.isPendingCloseOrClosing()
261 && am.getZKTable().isDisablingOrDisabledTable(hri.getTable())) {
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267 regionStates.updateRegionState(hri, State.OFFLINE);
268 am.deleteClosingOrClosedNode(hri, rit.getServerName());
269 am.offlineDisabledRegion(hri);
270 } else {
271 LOG.warn("THIS SHOULD NOT HAPPEN: unexpected region in transition "
272 + rit + " not to be assigned by SSH of server " + serverName);
273 }
274 }
275 } finally {
276 lock.unlock();
277 }
278 }
279 }
280
281 try {
282 am.assign(toAssignRegions);
283 } catch (InterruptedException ie) {
284 LOG.error("Caught " + ie + " during round-robin assignment");
285 throw (InterruptedIOException)new InterruptedIOException().initCause(ie);
286 }
287
288 if (this.shouldSplitHlog && this.distributedLogReplay) {
289
290 for (HRegionInfo hri : toAssignRegions) {
291 try {
292 if (!am.waitOnRegionToClearRegionsInTransition(hri, regionAssignmentWaitTimeout)) {
293
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295 LOG.warn("Region " + hri.getEncodedName()
296 + " didn't complete assignment in time");
297 }
298 } catch (InterruptedException ie) {
299 throw new InterruptedIOException("Caught " + ie
300 + " during waitOnRegionToClearRegionsInTransition");
301 }
302 }
303
304 this.services.getExecutorService().submit(
305 new LogReplayHandler(this.server, this.services, this.deadServers, this.serverName));
306 hasLogReplayWork = true;
307 }
308 } finally {
309 this.deadServers.finish(serverName);
310 }
311
312 if (!hasLogReplayWork) {
313 LOG.info("Finished processing of shutdown of " + serverName);
314 }
315 }
316
317 private void resubmit(final ServerName serverName, IOException ex) throws IOException {
318
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320 this.services.getExecutorService().submit((ServerShutdownHandler) this);
321 this.deadServers.add(serverName);
322 throw new IOException("failed log splitting for " + serverName + ", will retry", ex);
323 }
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335 public static boolean processDeadRegion(HRegionInfo hri, Result result,
336 AssignmentManager assignmentManager, CatalogTracker catalogTracker)
337 throws IOException {
338 boolean tablePresent = assignmentManager.getZKTable().isTablePresent(hri.getTable());
339 if (!tablePresent) {
340 LOG.info("The table " + hri.getTable()
341 + " was deleted. Hence not proceeding.");
342 return false;
343 }
344
345 boolean disabled = assignmentManager.getZKTable().isDisabledTable(hri.getTable());
346 if (disabled){
347 LOG.info("The table " + hri.getTable()
348 + " was disabled. Hence not proceeding.");
349 return false;
350 }
351 if (hri.isOffline() && hri.isSplit()) {
352
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355 return false;
356 }
357 boolean disabling = assignmentManager.getZKTable().isDisablingTable(hri.getTable());
358 if (disabling) {
359 LOG.info("The table " + hri.getTable()
360 + " is disabled. Hence not assigning region" + hri.getEncodedName());
361 return false;
362 }
363 return true;
364 }
365 }