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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.util.EnvironmentEdgeManager;
30 import org.apache.hadoop.util.StringUtils;
31
32 import com.google.common.base.Preconditions;
33
34
35
36
37 @InterfaceAudience.Private
38 class RegionMergeRequest implements Runnable {
39 static final Log LOG = LogFactory.getLog(RegionMergeRequest.class);
40 private final HRegion region_a;
41 private final HRegion region_b;
42 private final HRegionServer server;
43 private final boolean forcible;
44 private TableLock tableLock;
45 private final long masterSystemTime;
46
47 RegionMergeRequest(HRegion a, HRegion b, HRegionServer hrs, boolean forcible,
48 long masterSystemTime) {
49 Preconditions.checkNotNull(hrs);
50 this.region_a = a;
51 this.region_b = b;
52 this.server = hrs;
53 this.forcible = forcible;
54 this.masterSystemTime = masterSystemTime;
55 }
56
57 @Override
58 public String toString() {
59 return "MergeRequest,regions:" + region_a + ", " + region_b + ", forcible="
60 + forcible;
61 }
62
63 @Override
64 public void run() {
65 if (this.server.isStopping() || this.server.isStopped()) {
66 LOG.debug("Skipping merge because server is stopping="
67 + this.server.isStopping() + " or stopped=" + this.server.isStopped());
68 return;
69 }
70 try {
71 final long startTime = EnvironmentEdgeManager.currentTimeMillis();
72 RegionMergeTransaction mt = new RegionMergeTransaction(region_a,
73 region_b, forcible, masterSystemTime);
74
75
76
77 tableLock = server.getTableLockManager().readLock(region_a.getTableDesc().getTableName()
78 , "MERGE_REGIONS:" + region_a.getRegionNameAsString() + ", " + region_b.getRegionNameAsString());
79 try {
80 tableLock.acquire();
81 } catch (IOException ex) {
82 tableLock = null;
83 throw ex;
84 }
85
86
87
88 if (!mt.prepare(this.server)) return;
89 try {
90 mt.execute(this.server, this.server);
91 } catch (Exception e) {
92 if (this.server.isStopping() || this.server.isStopped()) {
93 LOG.info(
94 "Skip rollback/cleanup of failed merge of " + region_a + " and "
95 + region_b + " because server is"
96 + (this.server.isStopping() ? " stopping" : " stopped"), e);
97 return;
98 }
99 if (e instanceof DroppedSnapshotException) {
100 server.abort("Replay of WAL required. Forcing server shutdown", e);
101 return;
102 }
103 try {
104 LOG.warn("Running rollback/cleanup of failed merge of "
105 + region_a +" and "+ region_b + "; " + e.getMessage(), e);
106 if (mt.rollback(this.server, this.server)) {
107 LOG.info("Successful rollback of failed merge of "
108 + region_a +" and "+ region_b);
109 } else {
110 this.server.abort("Abort; we got an error after point-of-no-return"
111 + "when merging " + region_a + " and " + region_b);
112 }
113 } catch (RuntimeException ee) {
114 String msg = "Failed rollback of failed merge of "
115 + region_a +" and "+ region_b + " -- aborting server";
116
117
118 LOG.info(msg, ee);
119 this.server.abort(msg);
120 }
121 return;
122 }
123 LOG.info("Regions merged, hbase:meta updated, and report to master. region_a="
124 + region_a + ", region_b=" + region_b + ",merged region="
125 + mt.getMergedRegionInfo().getRegionNameAsString()
126 + ". Region merge took "
127 + StringUtils.formatTimeDiff(EnvironmentEdgeManager.currentTimeMillis(), startTime));
128 } catch (IOException ex) {
129 LOG.error("Merge failed " + this,
130 RemoteExceptionHandler.checkIOException(ex));
131 server.checkFileSystem();
132 } finally {
133 releaseTableLock();
134 }
135 }
136
137 protected void releaseTableLock() {
138 if (this.tableLock != null) {
139 try {
140 this.tableLock.release();
141 } catch (IOException ex) {
142 LOG.error("Could not release the table lock (something is really wrong). "
143 + "Aborting this server to avoid holding the lock forever.");
144 this.server.abort("Abort; we got an error when releasing the table lock "
145 + "on " + region_a.getRegionNameAsString());
146 }
147 }
148 }
149 }