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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
172 if (!this.server.isStopped()) {
173 hris = MetaReader.getServerUserRegions(this.server.getCatalogTracker(),
174 this.serverName);
175 }
176 break;
177 } catch (InterruptedException e) {
178 Thread.currentThread().interrupt();
179 throw (InterruptedIOException)new InterruptedIOException().initCause(e);
180 } catch (IOException ioe) {
181 LOG.info("Received exception accessing hbase:meta during server shutdown of " +
182 serverName + ", retrying hbase:meta read", ioe);
183 }
184 }
185 if (this.server.isStopped()) {
186 throw new IOException("Server is stopped");
187 }
188
189 try {
190 if (this.shouldSplitHlog) {
191 LOG.info("Splitting logs for " + serverName + " before assignment.");
192 if (this.distributedLogReplay) {
193 LOG.info("Mark regions in recovery before assignment.");
194 Set<ServerName> serverNames = new HashSet<ServerName>();
195 serverNames.add(serverName);
196 this.services.getMasterFileSystem().prepareLogReplay(serverNames);
197 } else {
198 this.services.getMasterFileSystem().splitLog(serverName);
199 }
200 am.getRegionStates().logSplit(serverName);
201 } else {
202 LOG.info("Skipping log splitting for " + serverName);
203 }
204 } catch (IOException ioe) {
205 resubmit(serverName, ioe);
206 }
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212 List<HRegionInfo> regionsInTransition = am.processServerShutdown(serverName);
213 LOG.info("Reassigning " + ((hris == null)? 0: hris.size()) +
214 " region(s) that " + (serverName == null? "null": serverName) +
215 " was carrying (and " + regionsInTransition.size() +
216 " regions(s) that were opening on this server)");
217
218 List<HRegionInfo> toAssignRegions = new ArrayList<HRegionInfo>();
219 toAssignRegions.addAll(regionsInTransition);
220
221
222 if (hris != null) {
223 RegionStates regionStates = am.getRegionStates();
224 for (Map.Entry<HRegionInfo, Result> e: hris.entrySet()) {
225 HRegionInfo hri = e.getKey();
226 if (regionsInTransition.contains(hri)) {
227 continue;
228 }
229 String encodedName = hri.getEncodedName();
230 Lock lock = am.acquireRegionLock(encodedName);
231 try {
232 RegionState rit = regionStates.getRegionTransitionState(hri);
233 if (processDeadRegion(hri, e.getValue(), am, server.getCatalogTracker())) {
234 ServerName addressFromAM = regionStates.getRegionServerOfRegion(hri);
235 if (addressFromAM != null && !addressFromAM.equals(this.serverName)) {
236
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238 LOG.info("Skip assigning region " + hri.getRegionNameAsString()
239 + " because it has been opened in " + addressFromAM.getServerName());
240 continue;
241 }
242 if (rit != null) {
243 if (rit.getServerName() != null && !rit.isOnServer(serverName)) {
244
245 LOG.info("Skip assigning region in transition on other server" + rit);
246 continue;
247 }
248 try{
249
250 LOG.info("Reassigning region with rs = " + rit + " and deleting zk node if exists");
251 ZKAssign.deleteNodeFailSilent(services.getZooKeeper(), hri);
252 regionStates.updateRegionState(hri, State.OFFLINE);
253 } catch (KeeperException ke) {
254 this.server.abort("Unexpected ZK exception deleting unassigned node " + hri, ke);
255 return;
256 }
257 } else if (regionStates.isRegionInState(
258 hri, State.SPLITTING_NEW, State.MERGING_NEW)) {
259 regionStates.regionOffline(hri);
260 }
261 toAssignRegions.add(hri);
262 } else if (rit != null) {
263 if (rit.isPendingCloseOrClosing()
264 && am.getZKTable().isDisablingOrDisabledTable(hri.getTable())) {
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270 regionStates.updateRegionState(hri, State.OFFLINE);
271 am.deleteClosingOrClosedNode(hri, rit.getServerName());
272 am.offlineDisabledRegion(hri);
273 } else {
274 LOG.warn("THIS SHOULD NOT HAPPEN: unexpected region in transition "
275 + rit + " not to be assigned by SSH of server " + serverName);
276 }
277 }
278 } finally {
279 lock.unlock();
280 }
281 }
282 }
283
284 try {
285 am.assign(toAssignRegions);
286 } catch (InterruptedException ie) {
287 LOG.error("Caught " + ie + " during round-robin assignment");
288 throw (InterruptedIOException)new InterruptedIOException().initCause(ie);
289 }
290
291 if (this.shouldSplitHlog && this.distributedLogReplay) {
292
293 for (HRegionInfo hri : toAssignRegions) {
294 try {
295 if (!am.waitOnRegionToClearRegionsInTransition(hri, regionAssignmentWaitTimeout)) {
296
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298 LOG.warn("Region " + hri.getEncodedName()
299 + " didn't complete assignment in time");
300 }
301 } catch (InterruptedException ie) {
302 throw new InterruptedIOException("Caught " + ie
303 + " during waitOnRegionToClearRegionsInTransition");
304 }
305 }
306
307 this.services.getExecutorService().submit(
308 new LogReplayHandler(this.server, this.services, this.deadServers, this.serverName));
309 hasLogReplayWork = true;
310 }
311 } finally {
312 this.deadServers.finish(serverName);
313 }
314
315 if (!hasLogReplayWork) {
316 LOG.info("Finished processing of shutdown of " + serverName);
317 }
318 }
319
320 private void resubmit(final ServerName serverName, IOException ex) throws IOException {
321
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323 this.services.getExecutorService().submit((ServerShutdownHandler) this);
324 this.deadServers.add(serverName);
325 throw new IOException("failed log splitting for " + serverName + ", will retry", ex);
326 }
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338 public static boolean processDeadRegion(HRegionInfo hri, Result result,
339 AssignmentManager assignmentManager, CatalogTracker catalogTracker)
340 throws IOException {
341 boolean tablePresent = assignmentManager.getZKTable().isTablePresent(hri.getTable());
342 if (!tablePresent) {
343 LOG.info("The table " + hri.getTable()
344 + " was deleted. Hence not proceeding.");
345 return false;
346 }
347
348 boolean disabled = assignmentManager.getZKTable().isDisabledTable(hri.getTable());
349 if (disabled){
350 LOG.info("The table " + hri.getTable()
351 + " was disabled. Hence not proceeding.");
352 return false;
353 }
354 if (hri.isOffline() && hri.isSplit()) {
355
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358 return false;
359 }
360 boolean disabling = assignmentManager.getZKTable().isDisablingTable(hri.getTable());
361 if (disabling) {
362 LOG.info("The table " + hri.getTable()
363 + " is disabled. Hence not assigning region" + hri.getEncodedName());
364 return false;
365 }
366 return true;
367 }
368 }