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19 package org.apache.hadoop.hbase.regionserver;
20
21 import java.io.IOException;
22
23 import org.apache.commons.logging.Log;
24 import org.apache.commons.logging.LogFactory;
25 import org.apache.hadoop.hbase.classification.InterfaceAudience;
26 import org.apache.hadoop.hbase.DroppedSnapshotException;
27 import org.apache.hadoop.hbase.RemoteExceptionHandler;
28 import org.apache.hadoop.hbase.master.TableLockManager.TableLock;
29 import org.apache.hadoop.hbase.security.User;
30 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
31 import org.apache.hadoop.util.StringUtils;
32
33 import com.google.common.base.Preconditions;
34
35
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37
38 @InterfaceAudience.Private
39 class RegionMergeRequest implements Runnable {
40 static final Log LOG = LogFactory.getLog(RegionMergeRequest.class);
41 private final HRegion region_a;
42 private final HRegion region_b;
43 private final HRegionServer server;
44 private final boolean forcible;
45 private TableLock tableLock;
46 private final long masterSystemTime;
47 private final User user;
48
49 RegionMergeRequest(HRegion a, HRegion b, HRegionServer hrs, boolean forcible,
50 long masterSystemTime, User user) {
51 Preconditions.checkNotNull(hrs);
52 this.region_a = a;
53 this.region_b = b;
54 this.server = hrs;
55 this.forcible = forcible;
56 this.masterSystemTime = masterSystemTime;
57 this.user = user;
58 }
59
60 @Override
61 public String toString() {
62 return "MergeRequest,regions:" + region_a + ", " + region_b + ", forcible="
63 + forcible;
64 }
65
66 @Override
67 public void run() {
68 if (this.server.isStopping() || this.server.isStopped()) {
69 LOG.debug("Skipping merge because server is stopping="
70 + this.server.isStopping() + " or stopped=" + this.server.isStopped());
71 return;
72 }
73 try {
74 final long startTime = EnvironmentEdgeManager.currentTimeMillis();
75 RegionMergeTransaction mt = new RegionMergeTransaction(region_a,
76 region_b, forcible, masterSystemTime);
77
78
79
80 tableLock = server.getTableLockManager().readLock(region_a.getTableDesc().getTableName()
81 , "MERGE_REGIONS:" + region_a.getRegionNameAsString() + ", " + region_b.getRegionNameAsString());
82 try {
83 tableLock.acquire();
84 } catch (IOException ex) {
85 tableLock = null;
86 throw ex;
87 }
88
89
90
91 if (!mt.prepare(this.server)) return;
92 try {
93 mt.execute(this.server, this.server, this.user);
94 } catch (Exception e) {
95 if (this.server.isStopping() || this.server.isStopped()) {
96 LOG.info(
97 "Skip rollback/cleanup of failed merge of " + region_a + " and "
98 + region_b + " because server is"
99 + (this.server.isStopping() ? " stopping" : " stopped"), e);
100 return;
101 }
102 if (e instanceof DroppedSnapshotException) {
103 server.abort("Replay of WAL required. Forcing server shutdown", e);
104 return;
105 }
106 try {
107 LOG.warn("Running rollback/cleanup of failed merge of "
108 + region_a +" and "+ region_b + "; " + e.getMessage(), e);
109 if (mt.rollback(this.server, this.server)) {
110 LOG.info("Successful rollback of failed merge of "
111 + region_a +" and "+ region_b);
112 } else {
113 this.server.abort("Abort; we got an error after point-of-no-return"
114 + "when merging " + region_a + " and " + region_b);
115 }
116 } catch (RuntimeException ee) {
117 String msg = "Failed rollback of failed merge of "
118 + region_a +" and "+ region_b + " -- aborting server";
119
120
121 LOG.info(msg, ee);
122 this.server.abort(msg);
123 }
124 return;
125 }
126 LOG.info("Regions merged, hbase:meta updated, and report to master. region_a="
127 + region_a + ", region_b=" + region_b + ",merged region="
128 + mt.getMergedRegionInfo().getRegionNameAsString()
129 + ". Region merge took "
130 + StringUtils.formatTimeDiff(EnvironmentEdgeManager.currentTimeMillis(), startTime));
131 } catch (IOException ex) {
132 LOG.error("Merge failed " + this,
133 RemoteExceptionHandler.checkIOException(ex));
134 server.checkFileSystem();
135 } finally {
136 releaseTableLock();
137 }
138 }
139
140 protected void releaseTableLock() {
141 if (this.tableLock != null) {
142 try {
143 this.tableLock.release();
144 } catch (IOException ex) {
145 LOG.error("Could not release the table lock (something is really wrong). "
146 + "Aborting this server to avoid holding the lock forever.");
147 this.server.abort("Abort; we got an error when releasing the table lock "
148 + "on " + region_a.getRegionNameAsString());
149 }
150 }
151 }
152 }