diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
index 570a5ba15f6..59d13fac7db 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
@@ -1843,9 +1843,10 @@ public class HRegionServer extends HasThread implements
       roller = ensureMetaWALRoller();
       wal = walFactory.getMetaWAL(regionInfo.getEncodedNameAsBytes());
     } else if (regionInfo == null) {
-      wal = walFactory.getWAL(UNSPECIFIED_REGION);
+      wal = walFactory.getWAL(UNSPECIFIED_REGION, null);
     } else {
-      wal = walFactory.getWAL(regionInfo.getEncodedNameAsBytes());
+      byte[] namespace = regionInfo.getTable().getNamespace();
+      wal = walFactory.getWAL(regionInfo.getEncodedNameAsBytes(), namespace);
     }
     roller.addWAL(wal);
     return wal;
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java
index bbbf9aed58e..49884812714 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java
@@ -1342,7 +1342,7 @@ public class HBaseFsck extends Configured implements Closeable {
     WAL wal = (new WALFactory(confForWAL,
         Collections.<WALActionsListener>singletonList(new MetricsWAL()),
         "hbck-meta-recovery-" + RandomStringUtils.randomNumeric(8))).
-        getWAL(metaHRI.getEncodedNameAsBytes());
+        getWAL(metaHRI.getEncodedNameAsBytes(), metaHRI.getTable().getNamespace());
     HRegion meta = HRegion.createHRegion(metaHRI, rootdir, c, metaDescriptor, wal);
     MasterFileSystem.setInfoFamilyCachingForMeta(metaDescriptor, true);
     return meta;
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HMerge.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HMerge.java
index e29384b9a28..c37f9522dee 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HMerge.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/HMerge.java
@@ -193,11 +193,13 @@ class HMerge {
       for (int i = 0; i < info.length - 1; i++) {
         if (currentRegion == null) {
           currentRegion = HRegion.openHRegion(conf, fs, this.rootDir, info[i], this.htd,
-              walFactory.getWAL(info[i].getEncodedNameAsBytes()));
+              walFactory.getWAL(info[i].getEncodedNameAsBytes(),
+                info[i].getTable().getNamespace()));
           currentSize = currentRegion.getLargestHStoreSize();
         }
         nextRegion = HRegion.openHRegion(conf, fs, this.rootDir, info[i + 1], this.htd,
-            walFactory.getWAL(info[i+1].getEncodedNameAsBytes()));
+            walFactory.getWAL(info[i + 1].getEncodedNameAsBytes(),
+              info[i + 1].getTable().getNamespace()));
         nextSize = nextRegion.getLargestHStoreSize();
 
         if ((currentSize + nextSize) <= (maxFilesize / 2)) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/MetaUtils.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/MetaUtils.java
index 1ff4967ac14..309bd4a7349 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/MetaUtils.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/MetaUtils.java
@@ -95,7 +95,9 @@ public class MetaUtils {
       this.walFactory = new WALFactory(walConf, null, logName);
     }
     final byte[] region = info.getEncodedNameAsBytes();
-    return info.isMetaRegion() ? walFactory.getMetaWAL(region) : walFactory.getWAL(region);
+    final byte[] namespace = info.getTable().getNamespace();
+    return info.isMetaRegion() ? walFactory.getMetaWAL(region) : walFactory.getWAL(region,
+      namespace);
   }
 
   /**
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/BoundedGroupingStrategy.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/BoundedGroupingStrategy.java
index c8f434fefb7..65c774ea4f4 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/BoundedGroupingStrategy.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/BoundedGroupingStrategy.java
@@ -42,7 +42,7 @@ public class BoundedGroupingStrategy implements RegionGroupingStrategy{
   private String[] groupNames;
 
   @Override
-  public String group(byte[] identifier) {
+  public String group(byte[] identifier, byte[] namespace) {
     String idStr = Bytes.toString(identifier);
     String groupName = groupNameCache.get(idStr);
     if (null == groupName) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DefaultWALProvider.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DefaultWALProvider.java
index be95e16b264..027e7a21306 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DefaultWALProvider.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DefaultWALProvider.java
@@ -118,7 +118,7 @@ public class DefaultWALProvider implements WALProvider {
   }
 
   @Override
-  public WAL getWAL(final byte[] identifier) throws IOException {
+  public WAL getWAL(final byte[] identifier, byte[] namespace) throws IOException {
     if (log == null) {
       // only lock when need to create wal, and need to lock since
       // creating hlog on fs is time consuming
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DisabledWALProvider.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DisabledWALProvider.java
index 10a097b82b5..04045ec6d70 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DisabledWALProvider.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/DisabledWALProvider.java
@@ -67,7 +67,7 @@ class DisabledWALProvider implements WALProvider {
   }
 
   @Override
-  public WAL getWAL(final byte[] identifier) throws IOException {
+  public WAL getWAL(final byte[] identifier, byte[] namespace) throws IOException {
     return disabled;
   }
 
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/NamespaceGroupingStrategy.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/NamespaceGroupingStrategy.java
new file mode 100644
index 00000000000..a450e7dfcf6
--- /dev/null
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/NamespaceGroupingStrategy.java
@@ -0,0 +1,52 @@
+/**
+ *
+ * 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.hbase.wal;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.NamespaceDescriptor;
+import org.apache.hadoop.hbase.classification.InterfaceAudience;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.wal.RegionGroupingProvider.RegionGroupingStrategy;
+
+/**
+ * A WAL grouping strategy based on namespace.
+ * Notice: the wal-group mapping might change if we support dynamic namespace updating later,
+ * and special attention needed if we support feature like group-based replication.
+ */
+@InterfaceAudience.Private
+public class NamespaceGroupingStrategy implements RegionGroupingStrategy {
+  String providerId;
+
+  @Override
+  public String group(byte[] identifier, byte[] namespace) {
+    String namespaceString;
+    if (namespace == null || namespace.length == 0) {
+      namespaceString = NamespaceDescriptor.DEFAULT_NAMESPACE_NAME_STR;
+    } else {
+      namespaceString = Bytes.toString(namespace);
+    }
+    return providerId + GROUP_NAME_DELIMITER + namespaceString;
+  }
+
+  @Override
+  public void init(Configuration config, String providerId) {
+    this.providerId = providerId;
+  }
+
+}
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/RegionGroupingProvider.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/RegionGroupingProvider.java
index 00a5651bbb8..288542893b8 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/RegionGroupingProvider.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/RegionGroupingProvider.java
@@ -65,12 +65,11 @@ class RegionGroupingProvider implements WALProvider {
    */
   public static interface RegionGroupingStrategy {
     String GROUP_NAME_DELIMITER = ".";
+
     /**
-     * Given an identifier, pick a group.
-     * the byte[] returned for a given group must always use the same instance, since we
-     * will be using it as a hash key.
+     * Given an identifier and a namespace, pick a group.
      */
-    String group(final byte[] identifier);
+    String group(final byte[] identifier, byte[] namespace);
     void init(Configuration config, String providerId);
   }
 
@@ -80,7 +79,8 @@ class RegionGroupingProvider implements WALProvider {
   static enum Strategies {
     defaultStrategy(BoundedGroupingStrategy.class),
     identity(IdentityGroupingStrategy.class),
-    bounded(BoundedGroupingStrategy.class);
+    bounded(BoundedGroupingStrategy.class),
+    namespace(NamespaceGroupingStrategy.class);
 
     final Class<? extends RegionGroupingStrategy> clazz;
     Strategies(Class<? extends RegionGroupingStrategy> clazz) {
@@ -200,12 +200,12 @@ class RegionGroupingProvider implements WALProvider {
   }
 
   @Override
-  public WAL getWAL(final byte[] identifier) throws IOException {
+  public WAL getWAL(final byte[] identifier, byte[] namespace) throws IOException {
     final String group;
     if (META_WAL_PROVIDER_ID.equals(this.providerId)) {
       group = META_WAL_GROUP_NAME;
     } else {
-      group = strategy.group(identifier);
+      group = strategy.group(identifier, namespace);
     }
     return getWAL(group);
   }
@@ -254,7 +254,7 @@ class RegionGroupingProvider implements WALProvider {
     @Override
     public void init(Configuration config, String providerId) {}
     @Override
-    public String group(final byte[] identifier) {
+    public String group(final byte[] identifier, final byte[] namespace) {
       return Bytes.toString(identifier);
     }
   }
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALFactory.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALFactory.java
index e430e064c36..0317b6683fa 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALFactory.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALFactory.java
@@ -224,9 +224,10 @@ public class WALFactory {
 
   /**
    * @param identifier may not be null, contents will not be altered
+   * @param namespace could be null, and will use default namespace if null
    */
-  public WAL getWAL(final byte[] identifier) throws IOException {
-    return provider.getWAL(identifier);
+  public WAL getWAL(final byte[] identifier, final byte[] namespace) throws IOException {
+    return provider.getWAL(identifier, namespace);
   }
 
   /**
@@ -246,7 +247,7 @@ public class WALFactory {
         metaProvider = this.metaProvider.get();
       }
     }
-    return metaProvider.getWAL(identifier);
+    return metaProvider.getWAL(identifier, null);
   }
 
   public Reader createReader(final FileSystem fs, final Path path) throws IOException {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALProvider.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALProvider.java
index b007ad2014c..2c500dcfea4 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALProvider.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALProvider.java
@@ -53,9 +53,10 @@ public interface WALProvider {
 
   /**
    * @param identifier may not be null. contents will not be altered.
+   * @param namespace could be null, and will use default namespace if null
    * @return a WAL for writing entries for the given region.
    */
-  WAL getWAL(final byte[] identifier) throws IOException;
+  WAL getWAL(final byte[] identifier, byte[] namespace) throws IOException;
 
   /**
    * persist outstanding WALs to storage and stop accepting new appends.
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java
index be5df716771..d471ec9651c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java
@@ -2569,7 +2569,7 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
     return (new WALFactory(confForWAL,
         Collections.<WALActionsListener>singletonList(new MetricsWAL()),
         "hregion-" + RandomStringUtils.randomNumeric(8))).
-        getWAL(hri.getEncodedNameAsBytes());
+        getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace());
   }
 
   /**
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestWALObserver.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestWALObserver.java
index a3c106dc9a4..8993255df10 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestWALObserver.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestWALObserver.java
@@ -164,7 +164,7 @@ public class TestWALObserver {
    */
   @Test
   public void testWALObserverWriteToWAL() throws Exception {
-    final WAL log = wals.getWAL(UNSPECIFIED_REGION);
+    final WAL log = wals.getWAL(UNSPECIFIED_REGION, null);
     verifyWritesSeen(log, getCoprocessor(log, SampleRegionWALObserver.class), false);
   }
 
@@ -175,7 +175,7 @@ public class TestWALObserver {
    */
   @Test
   public void testLegacyWALObserverWriteToWAL() throws Exception {
-    final WAL log = wals.getWAL(UNSPECIFIED_REGION);
+    final WAL log = wals.getWAL(UNSPECIFIED_REGION, null);
     verifyWritesSeen(log, getCoprocessor(log, SampleRegionWALObserver.Legacy.class), true);
   }
 
@@ -279,7 +279,7 @@ public class TestWALObserver {
 
     final Configuration newConf = HBaseConfiguration.create(this.conf);
 
-    final WAL wal = wals.getWAL(UNSPECIFIED_REGION);
+    final WAL wal = wals.getWAL(UNSPECIFIED_REGION, null);
     final SampleRegionWALObserver newApi = getCoprocessor(wal, SampleRegionWALObserver.class);
     newApi.setTestValues(TEST_TABLE, TEST_ROW, null, null, null, null, null, null);
     final SampleRegionWALObserver oldApi = getCoprocessor(wal,
@@ -351,7 +351,7 @@ public class TestWALObserver {
     final HTableDescriptor htd = createBasic3FamilyHTD(Bytes.toString(TEST_TABLE));
     final AtomicLong sequenceId = new AtomicLong(0);
 
-    WAL log = wals.getWAL(UNSPECIFIED_REGION);
+    WAL log = wals.getWAL(UNSPECIFIED_REGION, null);
     try {
       SampleRegionWALObserver cp = getCoprocessor(log, SampleRegionWALObserver.class);
 
@@ -396,7 +396,7 @@ public class TestWALObserver {
     final Configuration newConf = HBaseConfiguration.create(this.conf);
 
     // WAL wal = new WAL(this.fs, this.dir, this.oldLogDir, this.conf);
-    WAL wal = wals.getWAL(UNSPECIFIED_REGION);
+    WAL wal = wals.getWAL(UNSPECIFIED_REGION, null);
     // Put p = creatPutWith2Families(TEST_ROW);
     WALEdit edit = new WALEdit();
     long now = EnvironmentEdgeManager.currentTime();
@@ -421,7 +421,7 @@ public class TestWALObserver {
         FileSystem newFS = FileSystem.get(newConf);
         // Make a new wal for new region open.
         final WALFactory wals2 = new WALFactory(conf, null, currentTest.getMethodName()+"2");
-        WAL wal2 = wals2.getWAL(UNSPECIFIED_REGION);;
+        WAL wal2 = wals2.getWAL(UNSPECIFIED_REGION, null);;
         HRegion region = HRegion.openHRegion(newConf, FileSystem.get(newConf), hbaseRootDir,
             hri, htd, wal2, TEST_UTIL.getHBaseCluster().getRegionServer(0), null);
         long seqid2 = region.getOpenSeqNum();
@@ -449,7 +449,7 @@ public class TestWALObserver {
    */
   @Test
   public void testWALObserverLoaded() throws Exception {
-    WAL log = wals.getWAL(UNSPECIFIED_REGION);
+    WAL log = wals.getWAL(UNSPECIFIED_REGION, null);
     assertNotNull(getCoprocessor(log, SampleRegionWALObserver.class));
   }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/mapreduce/TestWALRecordReader.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/mapreduce/TestWALRecordReader.java
index 1fcb3668b47..64ef8fdf663 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/mapreduce/TestWALRecordReader.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/mapreduce/TestWALRecordReader.java
@@ -119,7 +119,7 @@ public class TestWALRecordReader {
   @Test
   public void testPartialRead() throws Exception {
     final WALFactory walfactory = new WALFactory(conf, null, getName());
-    WAL log = walfactory.getWAL(info.getEncodedNameAsBytes());
+    WAL log = walfactory.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace());
     // This test depends on timestamp being millisecond based and the filename of the WAL also
     // being millisecond based.
     long ts = System.currentTimeMillis();
@@ -182,7 +182,7 @@ public class TestWALRecordReader {
   @Test
   public void testWALRecordReader() throws Exception {
     final WALFactory walfactory = new WALFactory(conf, null, getName());
-    WAL log = walfactory.getWAL(info.getEncodedNameAsBytes());
+    WAL log = walfactory.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace());
     byte [] value = Bytes.toBytes("value");
     final AtomicLong sequenceId = new AtomicLong(0);
     WALEdit edit = new WALEdit();
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCacheOnWriteInSchema.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCacheOnWriteInSchema.java
index b7ebd23865f..da3c17d1088 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCacheOnWriteInSchema.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCacheOnWriteInSchema.java
@@ -174,7 +174,7 @@ public class TestCacheOnWriteInSchema {
     walFactory = new WALFactory(conf, null, id);
 
     region = TEST_UTIL.createLocalHRegion(info, htd,
-        walFactory.getWAL(info.getEncodedNameAsBytes()));
+        walFactory.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace()));
     store = new HStore(region, hcd, conf);
   }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultCompactSelection.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultCompactSelection.java
index 4969a59c83a..50b172228b5 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultCompactSelection.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultCompactSelection.java
@@ -100,8 +100,8 @@ public class TestDefaultCompactSelection extends TestCase {
     region = HBaseTestingUtility.createRegionAndWAL(info, basedir, conf, htd);
     HBaseTestingUtility.closeRegionAndWAL(region);
     Path tableDir = FSUtils.getTableDir(basedir, htd.getTableName());
-    region = new HRegion(tableDir, wals.getWAL(info.getEncodedNameAsBytes()), fs, conf, info, htd,
-        null);
+    region = new HRegion(tableDir, wals.getWAL(info.getEncodedNameAsBytes(), info.getTable()
+        .getNamespace()), fs, conf, info, htd, null);
 
     store = new HStore(region, hcd, conf);
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultMemStore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultMemStore.java
index e50260fcc25..d9995178284 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultMemStore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestDefaultMemStore.java
@@ -962,7 +962,7 @@ public class TestDefaultMemStore extends TestCase {
     desc.addFamily(new HColumnDescriptor("foo".getBytes()));
     HRegion r =
         HRegion.createHRegion(hri, testDir, conf, desc,
-            wFactory.getWAL(hri.getEncodedNameAsBytes()));
+            wFactory.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace()));
     HRegion.addRegionToMETA(meta, r);
     edge.setCurrentTimeMillis(1234 + 100);
     StringBuffer sb = new StringBuffer();
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java
index 4ed918cf91d..2cb3b38f505 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java
@@ -160,8 +160,8 @@ public class TestHMobStore {
     final Configuration walConf = new Configuration(conf);
     FSUtils.setRootDir(walConf, basedir);
     final WALFactory wals = new WALFactory(walConf, null, methodName);
-    region = new HRegion(tableDir, wals.getWAL(info.getEncodedNameAsBytes()), fs, conf,
-            info, htd, null);
+    region = new HRegion(tableDir, wals.getWAL(info.getEncodedNameAsBytes(),
+            info.getTable().getNamespace()), fs, conf, info, htd, null);
     store = new HMobStore(region, hcd, conf);
     if(testStore) {
       init(conf, hcd);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java
index a4804f1ec78..e96c6303a97 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java
@@ -362,7 +362,7 @@ public class TestHRegion {
     FSUtils.setRootDir(walConf, logDir);
     return (new WALFactory(walConf,
         Collections.<WALActionsListener>singletonList(new MetricsWAL()), callingMethod))
-        .getWAL(tableName.toBytes());
+        .getWAL(tableName.toBytes(), tableName.getNamespace());
   }
 
   /**
@@ -934,7 +934,7 @@ public class TestHRegion {
     final Configuration walConf = new Configuration(TEST_UTIL.getConfiguration());
     FSUtils.setRootDir(walConf, logDir);
     final WALFactory wals = new WALFactory(walConf, null, method);
-    final WAL wal = wals.getWAL(tableName.getName());
+    final WAL wal = wals.getWAL(tableName.getName(), tableName.getNamespace());
 
     this.region = initHRegion(tableName, HConstants.EMPTY_START_ROW,
       HConstants.EMPTY_END_ROW, method, CONF, false, Durability.USE_DEFAULT, wal, family);
@@ -4762,7 +4762,7 @@ public class TestHRegion {
     final Configuration walConf = new Configuration(conf);
     FSUtils.setRootDir(walConf, logDir);
     final WALFactory wals = new WALFactory(walConf, null, UUID.randomUUID().toString());
-    final WAL wal = spy(wals.getWAL(tableName.getName()));
+    final WAL wal = spy(wals.getWAL(tableName.getName(), tableName.getNamespace()));
     this.region = initHRegion(tableName, HConstants.EMPTY_START_ROW,
         HConstants.EMPTY_END_ROW, method, conf, false, tableDurability, wal,
         new byte[][] { family });
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionReplayEvents.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionReplayEvents.java
index c065ee78beb..c63f6bed2d3 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionReplayEvents.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionReplayEvents.java
@@ -158,8 +158,10 @@ public class TestHRegionReplayEvents {
       false, time, 1);
 
     wals = TestHRegion.createWALFactory(CONF, rootDir);
-    walPrimary = wals.getWAL(primaryHri.getEncodedNameAsBytes());
-    walSecondary = wals.getWAL(secondaryHri.getEncodedNameAsBytes());
+    walPrimary = wals.getWAL(primaryHri.getEncodedNameAsBytes(),
+        primaryHri.getTable().getNamespace());
+    walSecondary = wals.getWAL(secondaryHri.getEncodedNameAsBytes(),
+        secondaryHri.getTable().getNamespace());
 
     rss = mock(RegionServerServices.class);
     when(rss.getServerName()).thenReturn(ServerName.valueOf("foo", 1, 1));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestRegionMergeTransaction.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestRegionMergeTransaction.java
index b2115b34ea4..f238770e5a1 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestRegionMergeTransaction.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestRegionMergeTransaction.java
@@ -415,8 +415,9 @@ public class TestRegionMergeTransaction {
     HRegion a = HBaseTestingUtility.createRegionAndWAL(hri, testdir,
         TEST_UTIL.getConfiguration(), htd);
     HBaseTestingUtility.closeRegionAndWAL(a);
-    return HRegion.openHRegion(testdir, hri, htd, wals.getWAL(hri.getEncodedNameAsBytes()),
-        TEST_UTIL.getConfiguration());
+    return HRegion.openHRegion(testdir, hri, htd,
+      wals.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace()),
+      TEST_UTIL.getConfiguration());
   }
 
   private int countRows(final HRegion r) throws IOException {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestSplitTransaction.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestSplitTransaction.java
index 4f371bdb32a..26b32934497 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestSplitTransaction.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestSplitTransaction.java
@@ -380,7 +380,8 @@ public class TestSplitTransaction {
     HRegion r = HBaseTestingUtility.createRegionAndWAL(hri, testdir, TEST_UTIL.getConfiguration(),
         htd);
     HBaseTestingUtility.closeRegionAndWAL(r);
-    return HRegion.openHRegion(testdir, hri, htd, wals.getWAL(hri.getEncodedNameAsBytes()),
+    return HRegion.openHRegion(testdir, hri, htd,
+      wals.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace()),
       TEST_UTIL.getConfiguration());
   }
   
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStore.java
index a1a58bce15d..6b669a0198f 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStore.java
@@ -186,8 +186,8 @@ public class TestStore {
     final Configuration walConf = new Configuration(conf);
     FSUtils.setRootDir(walConf, basedir);
     final WALFactory wals = new WALFactory(walConf, null, methodName);
-    HRegion region = new HRegion(tableDir, wals.getWAL(info.getEncodedNameAsBytes()), fs, conf,
-        info, htd, null);
+    HRegion region = new HRegion(tableDir, wals.getWAL(info.getEncodedNameAsBytes(),
+            info.getTable().getNamespace()), fs, conf, info, htd, null);
 
     store = new HStore(region, hcd, conf);
     return store;
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileRefresherChore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileRefresherChore.java
index ed0ac25f16f..665c5468a0c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileRefresherChore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileRefresherChore.java
@@ -106,7 +106,9 @@ public class TestStoreFileRefresherChore {
     final Configuration walConf = new Configuration(conf);
     FSUtils.setRootDir(walConf, tableDir);
     final WALFactory wals = new WALFactory(walConf, null, "log_" + replicaId);
-    HRegion region = new HRegion(fs, wals.getWAL(info.getEncodedNameAsBytes()), conf, htd, null);
+    HRegion region =
+        new HRegion(fs, wals.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace()),
+            conf, htd, null);
 
     region.initialize();
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestDurability.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestDurability.java
index 94aa1069a09..72e433018e3 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestDurability.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestDurability.java
@@ -85,7 +85,7 @@ public class TestDurability {
   public void testDurability() throws Exception {
     final WALFactory wals = new WALFactory(CONF, null, "TestDurability");
     byte[] tableName = Bytes.toBytes("TestDurability");
-    final WAL wal = wals.getWAL(tableName);
+    final WAL wal = wals.getWAL(tableName, null);
     HRegion region = createHRegion(tableName, "region", wal, Durability.USE_DEFAULT);
     HRegion deferredRegion = createHRegion(tableName, "deferredRegion", wal, Durability.ASYNC_WAL);
 
@@ -148,7 +148,7 @@ public class TestDurability {
     // Setting up region
     final WALFactory wals = new WALFactory(CONF, null, "TestIncrement");
     byte[] tableName = Bytes.toBytes("TestIncrement");
-    final WAL wal = wals.getWAL(tableName);
+    final WAL wal = wals.getWAL(tableName, null);
     HRegion region = createHRegion(tableName, "increment", wal, Durability.USE_DEFAULT);
 
     // col1: amount = 1, 1 write back to WAL
@@ -206,7 +206,7 @@ public class TestDurability {
     // Setting up region
     final WALFactory wals = new WALFactory(CONF, null, "testIncrementWithReturnResultsSetToFalse");
     byte[] tableName = Bytes.toBytes("testIncrementWithReturnResultsSetToFalse");
-    final WAL wal = wals.getWAL(tableName);
+    final WAL wal = wals.getWAL(tableName, null);
     HRegion region = createHRegion(tableName, "increment", wal, Durability.USE_DEFAULT);
 
     Increment inc1 = new Increment(row1);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollAbort.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollAbort.java
index 4e07040b970..e990d836d63 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollAbort.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollAbort.java
@@ -190,7 +190,8 @@ public class TestLogRollAbort {
           TableName.valueOf(this.getClass().getName());
       HRegionInfo regioninfo = new HRegionInfo(tableName,
           HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW);
-      final WAL log = wals.getWAL(regioninfo.getEncodedNameAsBytes());
+      final WAL log = wals.getWAL(regioninfo.getEncodedNameAsBytes(),
+          regioninfo.getTable().getNamespace());
     
       final AtomicLong sequenceId = new AtomicLong(1);
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRolling.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRolling.java
index 6309e8921af..a5d366b0ac7 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRolling.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRolling.java
@@ -199,7 +199,7 @@ public class TestLogRolling  {
     final Configuration conf = TEST_UTIL.getConfiguration();
     final WALFactory wals = new WALFactory(conf, null,
         ServerName.valueOf("test.com",8080, 1).toString());
-    final WAL newLog = wals.getWAL(new byte[]{});
+    final WAL newLog = wals.getWAL(new byte[]{}, null);
     try {
       // Now roll the log before we write anything.
       newLog.rollWriter(true);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollingNoCluster.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollingNoCluster.java
index bc33fc035e8..ea565e15816 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollingNoCluster.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRollingNoCluster.java
@@ -65,7 +65,7 @@ public class TestLogRollingNoCluster {
     final Configuration conf = new Configuration(TEST_UTIL.getConfiguration());
     FSUtils.setRootDir(conf, dir);
     final WALFactory wals = new WALFactory(conf, null, TestLogRollingNoCluster.class.getName());
-    final WAL wal = wals.getWAL(new byte[]{});
+    final WAL wal = wals.getWAL(new byte[]{}, null);
     
     Appender [] appenders = null;
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestWALActionsListener.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestWALActionsListener.java
index 69482d16018..390587d8176 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestWALActionsListener.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestWALActionsListener.java
@@ -91,7 +91,7 @@ public class TestWALActionsListener {
     final AtomicLong sequenceId = new AtomicLong(1);
     HRegionInfo hri = new HRegionInfo(TableName.valueOf(SOME_BYTES),
              SOME_BYTES, SOME_BYTES, false);
-    final WAL wal = wals.getWAL(hri.getEncodedNameAsBytes());
+    final WAL wal = wals.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace());
 
     for (int i = 0; i < 20; i++) {
       byte[] b = Bytes.toBytes(i+"");
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationSourceManager.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationSourceManager.java
index fddee29df70..bbe1495c011 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationSourceManager.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationSourceManager.java
@@ -201,7 +201,7 @@ public class TestReplicationSourceManager {
     listeners.add(replication);
     final WALFactory wals = new WALFactory(utility.getConfiguration(), listeners,
         URLEncoder.encode("regionserver:60020", "UTF8"));
-    final WAL wal = wals.getWAL(hri.getEncodedNameAsBytes());
+    final WAL wal = wals.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace());
     final AtomicLong sequenceId = new AtomicLong(1);
     manager.init();
     HTableDescriptor htd = new HTableDescriptor(TableName.valueOf("tableame"));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationWALReaderManager.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationWALReaderManager.java
index 8586d33e3a1..41662a81b51 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationWALReaderManager.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestReplicationWALReaderManager.java
@@ -131,7 +131,7 @@ public class TestReplicationWALReaderManager {
     pathWatcher = new PathWatcher();
     listeners.add(pathWatcher);
     final WALFactory wals = new WALFactory(conf, listeners, tn.getMethodName());
-    log = wals.getWAL(info.getEncodedNameAsBytes());
+    log = wals.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace());
   }
 
   @After
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java
index 8688c616cfb..a1b2aa1c35c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java
@@ -275,7 +275,7 @@ public class TestMergeTool extends HBaseTestCase {
       // Close the region and delete the log
       HBaseTestingUtility.closeRegionAndWAL(regions[i]);
     }
-    WAL log = wals.getWAL(new byte[]{});
+    WAL log = wals.getWAL(new byte[]{}, null);
      // Merge Region 0 and Region 1
     HRegion merged = mergeAndVerify("merging regions 0 and 1 ",
       this.sourceRegions[0].getRegionNameAsString(),
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/IOTestProvider.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/IOTestProvider.java
index e06a587733d..6b1ca037650 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/IOTestProvider.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/IOTestProvider.java
@@ -108,7 +108,7 @@ public class IOTestProvider implements WALProvider {
   }
 
   @Override
-  public WAL getWAL(final byte[] identifier) throws IOException {
+  public WAL getWAL(final byte[] identifier, byte[] namespace) throws IOException {
    return log;
   }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestBoundedRegionGroupingStrategy.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestBoundedRegionGroupingStrategy.java
index 8b15150f280..c810f33fe07 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestBoundedRegionGroupingStrategy.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestBoundedRegionGroupingStrategy.java
@@ -172,7 +172,7 @@ public class TestBoundedRegionGroupingStrategy {
       int count = 0;
       // we know that this should see one of the wals more than once
       for (int i = 0; i < temp*8; i++) {
-        final WAL maybeNewWAL = wals.getWAL(Bytes.toBytes(random.nextInt()));
+        final WAL maybeNewWAL = wals.getWAL(Bytes.toBytes(random.nextInt()), null);
         LOG.info("Iteration " + i + ", checking wal " + maybeNewWAL);
         if (seen.add(maybeNewWAL)) {
           count++;
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestDefaultWALProvider.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestDefaultWALProvider.java
index cf0488ad616..c48f60bab7d 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestDefaultWALProvider.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestDefaultWALProvider.java
@@ -198,7 +198,7 @@ public class TestDefaultWALProvider {
       HRegionInfo hri2 = new HRegionInfo(htd2.getTableName(),
           HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW);
       // we want to mix edits from regions, so pick our own identifier.
-      final WAL log = wals.getWAL(UNSPECIFIED_REGION);
+      final WAL log = wals.getWAL(UNSPECIFIED_REGION, null);
 
       // Add a single edit and make sure that rolling won't remove the file
       // Before HBASE-3198 it used to delete it
@@ -265,7 +265,7 @@ public class TestDefaultWALProvider {
     localConf.set(WALFactory.WAL_PROVIDER, DefaultWALProvider.class.getName());
     final WALFactory wals = new WALFactory(localConf, null, currentTest.getMethodName());
     try {
-      final WAL wal = wals.getWAL(UNSPECIFIED_REGION);
+      final WAL wal = wals.getWAL(UNSPECIFIED_REGION, null);
       assertEquals(0, DefaultWALProvider.getNumRolledLogFiles(wal));
       HRegionInfo hri1 =
           new HRegionInfo(table1.getTableName(), HConstants.EMPTY_START_ROW,
@@ -351,10 +351,11 @@ public class TestDefaultWALProvider {
       final Set<WAL> seen = new HashSet<WAL>(1);
       final Random random = new Random();
       assertTrue("first attempt to add WAL from default provider should work.",
-          seen.add(wals.getWAL(Bytes.toBytes(random.nextInt()))));
+          seen.add(wals.getWAL(Bytes.toBytes(random.nextInt()), null)));
       for (int i = 0; i < 1000; i++) {
-        assertFalse("default wal provider is only supposed to return a single wal, which should " +
-            "compare as .equals itself.", seen.add(wals.getWAL(Bytes.toBytes(random.nextInt()))));
+        assertFalse("default wal provider is only supposed to return a single wal, which should "
+            + "compare as .equals itself.",
+          seen.add(wals.getWAL(Bytes.toBytes(random.nextInt()), null)));
       }
     } finally {
       wals.close();
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestSecureWAL.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestSecureWAL.java
index 847b206d980..a74fd847735 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestSecureWAL.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestSecureWAL.java
@@ -91,7 +91,8 @@ public class TestSecureWAL {
     final AtomicLong sequenceId = new AtomicLong(1);
 
     // Write the WAL
-    final WAL wal = wals.getWAL(regioninfo.getEncodedNameAsBytes());
+    final WAL wal =
+        wals.getWAL(regioninfo.getEncodedNameAsBytes(), regioninfo.getTable().getNamespace());
 
     for (int i = 0; i < total; i++) {
       WALEdit kvs = new WALEdit();
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALFactory.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALFactory.java
index e393c1365e6..875492cacbc 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALFactory.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALFactory.java
@@ -185,7 +185,8 @@ public class TestWALFactory {
     final AtomicLong sequenceId = new AtomicLong(1);
     for (int ii = 0; ii < howmany; ii++) {
       for (int i = 0; i < howmany; i++) {
-        final WAL log = wals.getWAL(infos[i].getEncodedNameAsBytes());
+        final WAL log =
+            wals.getWAL(infos[i].getEncodedNameAsBytes(), infos[i].getTable().getNamespace());
         for (int j = 0; j < howmany; j++) {
           WALEdit edit = new WALEdit();
           byte [] family = Bytes.toBytes("column");
@@ -246,7 +247,7 @@ public class TestWALFactory {
                   null,null, false);
       HTableDescriptor htd = new HTableDescriptor(tableName);
       htd.addFamily(new HColumnDescriptor(tableName.getName()));
-      final WAL wal = wals.getWAL(info.getEncodedNameAsBytes());
+      final WAL wal = wals.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace());
 
       for (int i = 0; i < total; i++) {
         WALEdit kvs = new WALEdit();
@@ -361,7 +362,8 @@ public class TestWALFactory {
     HRegionInfo regioninfo = new HRegionInfo(tableName,
              HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW, false);
 
-    final WAL wal = wals.getWAL(regioninfo.getEncodedNameAsBytes());
+    final WAL wal =
+        wals.getWAL(regioninfo.getEncodedNameAsBytes(), regioninfo.getTable().getNamespace());
     final AtomicLong sequenceId = new AtomicLong(1);
     final int total = 20;
 
@@ -498,7 +500,7 @@ public class TestWALFactory {
       }
       HRegionInfo info = new HRegionInfo(htd.getTableName(),
         row,Bytes.toBytes(Bytes.toString(row) + "1"), false);
-      final WAL log = wals.getWAL(info.getEncodedNameAsBytes());
+      final WAL log = wals.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace());
 
       final long txid = log.append(htd, info,
         new WALKey(info.getEncodedNameAsBytes(), htd.getTableName(), System.currentTimeMillis()),
@@ -556,7 +558,7 @@ public class TestWALFactory {
       }
       HRegionInfo hri = new HRegionInfo(htd.getTableName(),
           HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW);
-      final WAL log = wals.getWAL(hri.getEncodedNameAsBytes());
+      final WAL log = wals.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace());
       final long txid = log.append(htd, hri,
         new WALKey(hri.getEncodedNameAsBytes(), htd.getTableName(), System.currentTimeMillis()),
         cols, sequenceId, true, null);
@@ -605,7 +607,7 @@ public class TestWALFactory {
 
     HRegionInfo hri = new HRegionInfo(tableName,
         HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW);
-    final WAL log = wals.getWAL(hri.getEncodedNameAsBytes());
+    final WAL log = wals.getWAL(hri.getEncodedNameAsBytes(), hri.getTable().getNamespace());
     log.registerWALActionsListener(visitor);
     for (int i = 0; i < COL_COUNT; i++) {
       WALEdit cols = new WALEdit();
@@ -634,7 +636,7 @@ public class TestWALFactory {
   @Test
   public void testWALCoprocessorLoaded() throws Exception {
     // test to see whether the coprocessor is loaded or not.
-    WALCoprocessorHost host = wals.getWAL(UNSPECIFIED_REGION).getCoprocessorHost();
+    WALCoprocessorHost host = wals.getWAL(UNSPECIFIED_REGION, null).getCoprocessorHost();
     Coprocessor c = host.findCoprocessor(SampleRegionWALObserver.class.getName());
     assertNotNull(c);
   }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALMethods.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALMethods.java
index 0c03019de93..bfe5d5e85ff 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALMethods.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALMethods.java
@@ -80,7 +80,7 @@ public class TestWALMethods {
 
     final Configuration walConf = new Configuration(util.getConfiguration());
     FSUtils.setRootDir(walConf, regiondir);
-    (new WALFactory(walConf, null, "dummyLogName")).getWAL(new byte[]{});
+    (new WALFactory(walConf, null, "dummyLogName")).getWAL(new byte[] {}, null);
 
     NavigableSet<Path> files = WALSplitter.getSplitEditFilesSorted(fs, regiondir);
     assertEquals(7, files.size());
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALReaderOnSecureWAL.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALReaderOnSecureWAL.java
index 52e28eb9bcf..415d626b62c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALReaderOnSecureWAL.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALReaderOnSecureWAL.java
@@ -109,7 +109,8 @@ public class TestWALReaderOnSecureWAL {
       final AtomicLong sequenceId = new AtomicLong(1);
 
       // Write the WAL
-      WAL wal = wals.getWAL(regioninfo.getEncodedNameAsBytes());
+      WAL wal =
+          wals.getWAL(regioninfo.getEncodedNameAsBytes(), regioninfo.getTable().getNamespace());
       for (int i = 0; i < total; i++) {
         WALEdit kvs = new WALEdit();
         kvs.add(new KeyValue(row, family, Bytes.toBytes(i), value));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALSplit.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALSplit.java
index a32aede16c0..4b70ab67512 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALSplit.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/TestWALSplit.java
@@ -1073,7 +1073,7 @@ public class TestWALSplit {
     REGIONS.add(regionName);
     generateWALs(-1);
 
-    wals.getWAL(Bytes.toBytes(regionName));
+    wals.getWAL(Bytes.toBytes(regionName), null);
     FileStatus[] logfiles = fs.listStatus(WALDIR);
     assertTrue("There should be some log file",
       logfiles != null && logfiles.length > 0);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/WALPerformanceEvaluation.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/WALPerformanceEvaluation.java
index 28c68b3818f..64bf319559c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/WALPerformanceEvaluation.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/wal/WALPerformanceEvaluation.java
@@ -485,7 +485,8 @@ public final class WALPerformanceEvaluation extends Configured implements Tool {
     // Initialize HRegion
     HRegionInfo regionInfo = new HRegionInfo(htd.getTableName());
     // Initialize WAL
-    final WAL wal = wals.getWAL(regionInfo.getEncodedNameAsBytes());
+    final WAL wal =
+        wals.getWAL(regionInfo.getEncodedNameAsBytes(), regionInfo.getTable().getNamespace());
     // If we haven't already, attach a listener to this wal to handle rolls and metrics.
     if (walsListenedTo.add(wal)) {
       roller.addWAL(wal);