HDFS-7296. HdfsConstants#MEMORY_STORAGE_POLICY_ID and HdfsConstants#MEMORY_STORAGE_POLICY_ID are missing in branch-2. Contributed by Jing Zhao.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSOutputStream.java

@@ -454,8 +454,8 @@ public class DFSOutputStream extends FSOutputSummer
     }
     
     private boolean initLazyPersist(HdfsFileStatus stat) {
-      final BlockStoragePolicy lpPolicy =
-          blockStoragePolicySuite.getPolicy("LAZY_PERSIST");
+      final BlockStoragePolicy lpPolicy = blockStoragePolicySuite
+          .getPolicy(HdfsConstants.MEMORY_STORAGE_POLICY_NAME);
       return lpPolicy != null &&
              stat.getStoragePolicy() == lpPolicy.getId();
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/HdfsConstants.java

@@ -166,14 +166,14 @@ public class HdfsConstants {
   public static final String SEPARATOR_DOT_SNAPSHOT_DIR_SEPARATOR
       = Path.SEPARATOR + DOT_SNAPSHOT_DIR + Path.SEPARATOR;
 
+  public static final String MEMORY_STORAGE_POLICY_NAME = "LAZY_PERSIST";
   public static final String ALLSSD_STORAGE_POLICY_NAME = "ALL_SSD";
   public static final String ONESSD_STORAGE_POLICY_NAME = "ONE_SSD";
   public static final String HOT_STORAGE_POLICY_NAME = "HOT";
   public static final String WARM_STORAGE_POLICY_NAME = "WARM";
   public static final String COLD_STORAGE_POLICY_NAME = "COLD";
-  public static final String LAZY_PERSIST_STORAGE_POLICY_NAME = "LAZY_PERSIST";
 
-  public static final byte LAZY_PERSIST_STORAGE_POLICY_ID = 15;
+  public static final byte MEMORY_STORAGE_POLICY_ID = 15;
   public static final byte ALLSSD_STORAGE_POLICY_ID = 12;
   public static final byte ONESSD_STORAGE_POLICY_ID = 10;
   public static final byte HOT_STORAGE_POLICY_ID = 7;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockStoragePolicySuite.java

@@ -45,9 +45,9 @@ public class BlockStoragePolicySuite {
   public static BlockStoragePolicySuite createDefaultSuite() {
     final BlockStoragePolicy[] policies =
         new BlockStoragePolicy[1 << ID_BIT_LENGTH];
-    final byte lazyPersistId = HdfsConstants.LAZY_PERSIST_STORAGE_POLICY_ID;
+    final byte lazyPersistId = HdfsConstants.MEMORY_STORAGE_POLICY_ID;
     policies[lazyPersistId] = new BlockStoragePolicy(lazyPersistId, 
-        HdfsConstants.LAZY_PERSIST_STORAGE_POLICY_NAME,
+        HdfsConstants.MEMORY_STORAGE_POLICY_NAME,
         new StorageType[]{StorageType.RAM_DISK, StorageType.DISK},
         new StorageType[]{StorageType.DISK},
         new StorageType[]{StorageType.DISK},

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockStoragePolicy.java

@@ -71,7 +71,7 @@ public class TestBlockStoragePolicy {
   static final byte HOT  = HdfsConstants.HOT_STORAGE_POLICY_ID;
   static final byte ONESSD  = HdfsConstants.ONESSD_STORAGE_POLICY_ID;
   static final byte ALLSSD  = HdfsConstants.ALLSSD_STORAGE_POLICY_ID;
-  static final byte LAZY_PERSIST  = HdfsConstants.LAZY_PERSIST_STORAGE_POLICY_ID;
+  static final byte LAZY_PERSIST  = HdfsConstants.MEMORY_STORAGE_POLICY_ID;
 
   @Test (timeout=300000)
   public void testConfigKeyEnabled() throws IOException {