HDFS-7056. Snapshot support for truncate. Contributed by Konstantin Shvachko and Plamen Jeliazkov.

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -21,6 +21,8 @@ Release 2.7.0 - UNRELEASED
 
     HDFS-3107. Introduce truncate. (Plamen Jeliazkov via shv)
 
+    HDFS-7056. Snapshot support for truncate. (Plamen Jeliazkov and shv)
+
   IMPROVEMENTS
 
     HDFS-7055. Add tracing to DFSInputStream (cmccabe)

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

@@ -537,7 +537,7 @@ public interface ClientProtocol {
    * @param src  existing file
    * @param newLength  the target size
    *
-   * @return true if and client does not need to wait for block recovery,
+   * @return true if client does not need to wait for block recovery,
    * false if client needs to wait for block recovery.
    *
    * @throws AccessControlException If access is denied

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/InterDatanodeProtocolServerSideTranslatorPB.java

@@ -76,8 +76,8 @@ public class InterDatanodeProtocolServerSideTranslatorPB implements
     final String storageID;
     try {
       storageID = impl.updateReplicaUnderRecovery(
-          PBHelper.convert(request.getBlock()),
+          PBHelper.convert(request.getBlock()), request.getRecoveryId(),
-          request.getRecoveryId(), request.getNewLength());
+          request.getNewBlockId(), request.getNewLength());
     } catch (IOException e) {
       throw new ServiceException(e);
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/InterDatanodeProtocolTranslatorPB.java

@@ -102,11 +102,12 @@ public class InterDatanodeProtocolTranslatorPB implements
 
   @Override
   public String updateReplicaUnderRecovery(ExtendedBlock oldBlock,
-      long recoveryId, long newLength) throws IOException {
+      long recoveryId, long newBlockId, long newLength) throws IOException {
     UpdateReplicaUnderRecoveryRequestProto req = 
         UpdateReplicaUnderRecoveryRequestProto.newBuilder()
         .setBlock(PBHelper.convert(oldBlock))
-        .setNewLength(newLength).setRecoveryId(recoveryId).build();
+        .setNewLength(newLength).setNewBlockId(newBlockId)
+        .setRecoveryId(recoveryId).build();
     try {
       return rpcProxy.updateReplicaUnderRecovery(NULL_CONTROLLER, req
           ).getStorageUuid();

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/PBHelper.java

@@ -608,16 +608,19 @@ public class PBHelper {
       return null;
     }
     LocatedBlockProto lb = PBHelper.convert((LocatedBlock)b);
-    return RecoveringBlockProto.newBuilder().setBlock(lb)
+    RecoveringBlockProto.Builder builder = RecoveringBlockProto.newBuilder();
-        .setNewGenStamp(b.getNewGenerationStamp())
+    builder.setBlock(lb).setNewGenStamp(b.getNewGenerationStamp());
-        .setTruncateFlag(b.getTruncateFlag()).build();
+    if(b.getNewBlock() != null)
+      builder.setTruncateBlock(PBHelper.convert(b.getNewBlock()));
+    return builder.build();
   }
 
   public static RecoveringBlock convert(RecoveringBlockProto b) {
     ExtendedBlock block = convert(b.getBlock().getB());
     DatanodeInfo[] locs = convert(b.getBlock().getLocsList());
-    return new RecoveringBlock(block, locs, b.getNewGenStamp(),
+    return (b.hasTruncateBlock()) ?
-        b.getTruncateFlag());
+        new RecoveringBlock(block, locs, PBHelper.convert(b.getTruncateBlock())) :
+        new RecoveringBlock(block, locs, b.getNewGenStamp());
   }
   
   public static DatanodeInfoProto.AdminState convert(

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

@@ -54,6 +54,11 @@ public class BlockInfoUnderConstruction extends BlockInfo {
    */
   private long blockRecoveryId = 0;
 
+  /**
+   * The block source to use in the event of copy-on-write truncate.
+   */
+  private Block truncateBlock;
+
   /**
    * ReplicaUnderConstruction contains information about replicas while
    * they are under construction.
@@ -229,6 +234,15 @@ public class BlockInfoUnderConstruction extends BlockInfo {
     return blockRecoveryId;
   }
 
+  /** Get recover block */
+  public Block getTruncateBlock() {
+    return truncateBlock;
+  }
+
+  public void setTruncateBlock(Block recoveryBlock) {
+    this.truncateBlock = recoveryBlock;
+  }
+
   /**
    * Process the recorded replicas. When about to commit or finish the
    * pipeline recovery sort out bad replicas.
@@ -273,11 +287,7 @@ public class BlockInfoUnderConstruction extends BlockInfo {
    * make it primary.
    */
   public void initializeBlockRecovery(long recoveryId) {
-    initializeBlockRecovery(BlockUCState.UNDER_RECOVERY, recoveryId);
+    setBlockUCState(BlockUCState.UNDER_RECOVERY);
-  }
-
-  public void initializeBlockRecovery(BlockUCState s, long recoveryId) {
-    setBlockUCState(s);
     blockRecoveryId = recoveryId;
     if (replicas.size() == 0) {
       NameNode.blockStateChangeLog.warn("BLOCK*"

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

@@ -700,13 +700,14 @@ public class BlockManager {
    * The client is supposed to allocate a new block with the next call.
    *
    * @param bc file
+   * @param bytesToRemove num of bytes to remove from block
    * @return the last block locations if the block is partial or null otherwise
    */
   public LocatedBlock convertLastBlockToUnderConstruction(
-      BlockCollection bc) throws IOException {
+      BlockCollection bc, long bytesToRemove) throws IOException {
     BlockInfo oldBlock = bc.getLastBlock();
     if(oldBlock == null ||
-        bc.getPreferredBlockSize() == oldBlock.getNumBytes())
+       bc.getPreferredBlockSize() == oldBlock.getNumBytes() - bytesToRemove)
       return null;
     assert oldBlock == getStoredBlock(oldBlock) :
       "last block of the file is not in blocksMap";

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

@@ -32,7 +32,6 @@ import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.protocol.*;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
 import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor.BlockTargetPair;
-import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
 import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor.CachedBlocksList;
 import org.apache.hadoop.hdfs.server.namenode.CachedBlock;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
@@ -1432,26 +1431,37 @@ public class DatanodeManager {
                 recoveryLocations.add(storages[i]);
               }
             }
+            // If we are performing a truncate recovery than set recovery fields
+            // to old block.
+            boolean truncateRecovery = b.getTruncateBlock() != null;
+            boolean copyOnTruncateRecovery = truncateRecovery &&
+                b.getTruncateBlock().getBlockId() != b.getBlockId();
+            ExtendedBlock primaryBlock = (copyOnTruncateRecovery) ?
+                new ExtendedBlock(blockPoolId, b.getTruncateBlock()) :
+                new ExtendedBlock(blockPoolId, b);
             // If we only get 1 replica after eliminating stale nodes, then choose all
             // replicas for recovery and let the primary data node handle failures.
+            DatanodeInfo[] recoveryInfos;
             if (recoveryLocations.size() > 1) {
               if (recoveryLocations.size() != storages.length) {
                 LOG.info("Skipped stale nodes for recovery : " +
                     (storages.length - recoveryLocations.size()));
               }
-              boolean isTruncate = b.getBlockUCState().equals(
+              recoveryInfos =
-                  HdfsServerConstants.BlockUCState.BEING_TRUNCATED);
+                  DatanodeStorageInfo.toDatanodeInfos(recoveryLocations);
-              brCommand.add(new RecoveringBlock(
-                  new ExtendedBlock(blockPoolId, b),
-                  DatanodeStorageInfo.toDatanodeInfos(recoveryLocations),
-                  b.getBlockRecoveryId(), isTruncate));
             } else {
               // If too many replicas are stale, then choose all replicas to participate
               // in block recovery.
-              brCommand.add(new RecoveringBlock(
+              recoveryInfos = DatanodeStorageInfo.toDatanodeInfos(storages);
-                  new ExtendedBlock(blockPoolId, b),
+            }
-                  DatanodeStorageInfo.toDatanodeInfos(storages),
+            if(truncateRecovery) {
-                  b.getBlockRecoveryId()));
+              Block recoveryBlock = (copyOnTruncateRecovery) ? b :
+                  b.getTruncateBlock();
+              brCommand.add(new RecoveringBlock(primaryBlock, recoveryInfos,
+                                                recoveryBlock));
+            } else {
+              brCommand.add(new RecoveringBlock(primaryBlock, recoveryInfos,
+                                                b.getBlockRecoveryId()));
             }
           }
           return new DatanodeCommand[] { brCommand };

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/HdfsServerConstants.java

@@ -299,13 +299,6 @@ public final class HdfsServerConstants {
      * which synchronizes the existing replicas contents.
      */
     UNDER_RECOVERY,
-    /**
-     * The block is being truncated.<br>
-     * When a file is truncated its last block may need to be truncated
-     * and needs to go through a recovery procedure,
-     * which synchronizes the existing replicas contents.
-     */
-    BEING_TRUNCATED,
     /**
      * The block is committed.<br>
      * The client reported that all bytes are written to data-nodes

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -2537,14 +2537,16 @@ public class DataNode extends ReconfigurableBase
    */
   @Override // InterDatanodeProtocol
   public String updateReplicaUnderRecovery(final ExtendedBlock oldBlock,
-      final long recoveryId, final long newLength) throws IOException {
+      final long recoveryId, final long newBlockId, final long newLength)
+      throws IOException {
     final String storageID = data.updateReplicaUnderRecovery(oldBlock,
-        recoveryId, newLength);
+        recoveryId, newBlockId, newLength);
     // Notify the namenode of the updated block info. This is important
     // for HA, since otherwise the standby node may lose track of the
     // block locations until the next block report.
     ExtendedBlock newBlock = new ExtendedBlock(oldBlock);
     newBlock.setGenerationStamp(recoveryId);
+    newBlock.setBlockId(newBlockId);
     newBlock.setNumBytes(newLength);
     notifyNamenodeReceivedBlock(newBlock, "", storageID);
     return storageID;
@@ -2566,10 +2568,12 @@ public class DataNode extends ReconfigurableBase
       this.rInfo = rInfo;
     }
 
-    void updateReplicaUnderRecovery(String bpid, long recoveryId, long newLength 
+    void updateReplicaUnderRecovery(String bpid, long recoveryId,
-        ) throws IOException {
+                                    long newBlockId, long newLength)
+        throws IOException {
       final ExtendedBlock b = new ExtendedBlock(bpid, rInfo);
-      storageID = datanode.updateReplicaUnderRecovery(b, recoveryId, newLength);
+      storageID = datanode.updateReplicaUnderRecovery(b, recoveryId, newBlockId,
+          newLength);
     }
 
     @Override
@@ -2653,6 +2657,10 @@ public class DataNode extends ReconfigurableBase
       getActiveNamenodeForBP(block.getBlockPoolId());
 
     long recoveryId = rBlock.getNewGenerationStamp();
+    boolean isTruncateRecovery = rBlock.getNewBlock() != null;
+    long blockId = (isTruncateRecovery) ?
+        rBlock.getNewBlock().getBlockId() : block.getBlockId();
+
     if (LOG.isDebugEnabled()) {
       LOG.debug("block=" + block + ", (length=" + block.getNumBytes()
           + "), syncList=" + syncList);
@@ -2686,7 +2694,7 @@ public class DataNode extends ReconfigurableBase
     // Calculate list of nodes that will participate in the recovery
     // and the new block size
     List<BlockRecord> participatingList = new ArrayList<BlockRecord>();
-    final ExtendedBlock newBlock = new ExtendedBlock(bpid, block.getBlockId(),
+    final ExtendedBlock newBlock = new ExtendedBlock(bpid, blockId,
         -1, recoveryId);
     switch(bestState) {
     case FINALIZED:
@@ -2698,10 +2706,7 @@ public class DataNode extends ReconfigurableBase
                       r.rInfo.getNumBytes() == finalizedLength)
           participatingList.add(r);
       }
-      if(rBlock.getTruncateFlag())
+      newBlock.setNumBytes(finalizedLength);
-        newBlock.setNumBytes(rBlock.getBlock().getNumBytes());
-      else
-        newBlock.setNumBytes(finalizedLength);
       break;
     case RBW:
     case RWR:
@@ -2713,21 +2718,21 @@ public class DataNode extends ReconfigurableBase
           participatingList.add(r);
         }
       }
-      if(rBlock.getTruncateFlag())
+      newBlock.setNumBytes(minLength);
-        newBlock.setNumBytes(rBlock.getBlock().getNumBytes());
-      else
-        newBlock.setNumBytes(minLength);
       break;
     case RUR:
     case TEMPORARY:
       assert false : "bad replica state: " + bestState;
     }
+    if(isTruncateRecovery)
+      newBlock.setNumBytes(rBlock.getNewBlock().getNumBytes());
 
     List<DatanodeID> failedList = new ArrayList<DatanodeID>();
     final List<BlockRecord> successList = new ArrayList<BlockRecord>();
     for(BlockRecord r : participatingList) {
       try {
-        r.updateReplicaUnderRecovery(bpid, recoveryId, newBlock.getNumBytes());
+        r.updateReplicaUnderRecovery(bpid, recoveryId, blockId,
+            newBlock.getNumBytes());
         successList.add(r);
       } catch (IOException e) {
         InterDatanodeProtocol.LOG.warn("Failed to updateBlock (newblock="

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/FsDatasetSpi.java

@@ -419,7 +419,7 @@ public interface FsDatasetSpi<V extends FsVolumeSpi> extends FSDatasetMBean {
    * @return the ID of storage that stores the block
    */
   public String updateReplicaUnderRecovery(ExtendedBlock oldBlock,
-      long recoveryId, long newLength) throws IOException;
+      long recoveryId, long newBlockId, long newLength) throws IOException;
 
   /**
    * add new block pool ID

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/FsDatasetImpl.java

@@ -687,6 +687,12 @@ class FsDatasetImpl implements FsDatasetSpi<FsVolumeImpl> {
     final File destDir = DatanodeUtil.idToBlockDir(destRoot, blockId);
     final File dstFile = new File(destDir, srcFile.getName());
     final File dstMeta = FsDatasetUtil.getMetaFile(dstFile, genStamp);
+    return copyBlockFiles(srcMeta, srcFile, dstMeta, dstFile, calculateChecksum);
+  }
+
+  static File[] copyBlockFiles(File srcMeta, File srcFile, File dstMeta,
+                               File dstFile, boolean calculateChecksum)
+      throws IOException {
     if (calculateChecksum) {
       computeChecksum(srcMeta, dstMeta, srcFile);
     } else {
@@ -2217,6 +2223,7 @@ class FsDatasetImpl implements FsDatasetSpi<FsVolumeImpl> {
   public synchronized String updateReplicaUnderRecovery(
                                     final ExtendedBlock oldBlock,
                                     final long recoveryId,
+                                    final long newBlockId,
                                     final long newlength) throws IOException {
     //get replica
     final String bpid = oldBlock.getBlockPoolId();
@@ -2249,13 +2256,26 @@ class FsDatasetImpl implements FsDatasetSpi<FsVolumeImpl> {
 
     //update replica
     final FinalizedReplica finalized = updateReplicaUnderRecovery(oldBlock
-        .getBlockPoolId(), (ReplicaUnderRecovery) replica, recoveryId, newlength);
+        .getBlockPoolId(), (ReplicaUnderRecovery) replica, recoveryId,
-    assert finalized.getBlockId() == oldBlock.getBlockId()
+        newBlockId, newlength);
-        && finalized.getGenerationStamp() == recoveryId
+
-        && finalized.getNumBytes() == newlength
+    boolean copyTruncate = newBlockId != oldBlock.getBlockId();
-        : "Replica information mismatched: oldBlock=" + oldBlock
+    if(!copyTruncate) {
-            + ", recoveryId=" + recoveryId + ", newlength=" + newlength
+      assert finalized.getBlockId() == oldBlock.getBlockId()
-            + ", finalized=" + finalized;
+          && finalized.getGenerationStamp() == recoveryId
+          && finalized.getNumBytes() == newlength
+          : "Replica information mismatched: oldBlock=" + oldBlock
+              + ", recoveryId=" + recoveryId + ", newlength=" + newlength
+              + ", newBlockId=" + newBlockId + ", finalized=" + finalized;
+    } else {
+      assert finalized.getBlockId() == oldBlock.getBlockId()
+          && finalized.getGenerationStamp() == oldBlock.getGenerationStamp()
+          && finalized.getNumBytes() == oldBlock.getNumBytes()
+          : "Finalized and old information mismatched: oldBlock=" + oldBlock
+              + ", genStamp=" + oldBlock.getGenerationStamp()
+              + ", len=" + oldBlock.getNumBytes()
+              + ", finalized=" + finalized;
+    }
 
     //check replica files after update
     checkReplicaFiles(finalized);
@@ -2268,6 +2288,7 @@ class FsDatasetImpl implements FsDatasetSpi<FsVolumeImpl> {
                                           String bpid,
                                           ReplicaUnderRecovery rur,
                                           long recoveryId,
+                                          long newBlockId,
                                           long newlength) throws IOException {
     //check recovery id
     if (rur.getRecoveryID() != recoveryId) {
@@ -2275,26 +2296,63 @@ class FsDatasetImpl implements FsDatasetSpi<FsVolumeImpl> {
           + ", rur=" + rur);
     }
 
+    boolean copyOnTruncate = newBlockId > 0L && rur.getBlockId() != newBlockId;
+    File blockFile;
+    File metaFile;
     // bump rur's GS to be recovery id
-    bumpReplicaGS(rur, recoveryId);
+    if(!copyOnTruncate) {
+      bumpReplicaGS(rur, recoveryId);
+      blockFile = rur.getBlockFile();
+      metaFile = rur.getMetaFile();
+    } else {
+      File[] copiedReplicaFiles =
+          copyReplicaWithNewBlockIdAndGS(rur, bpid, newBlockId, recoveryId);
+      blockFile = copiedReplicaFiles[1];
+      metaFile = copiedReplicaFiles[0];
+    }
 
     //update length
-    final File replicafile = rur.getBlockFile();
     if (rur.getNumBytes() < newlength) {
       throw new IOException("rur.getNumBytes() < newlength = " + newlength
           + ", rur=" + rur);
     }
     if (rur.getNumBytes() > newlength) {
       rur.unlinkBlock(1);
-      truncateBlock(replicafile, rur.getMetaFile(), rur.getNumBytes(), newlength);
+      truncateBlock(blockFile, metaFile, rur.getNumBytes(), newlength);
-      // update RUR with the new length
+      if(!copyOnTruncate) {
-      rur.setNumBytes(newlength);
+        // update RUR with the new length
+        rur.setNumBytes(newlength);
+      } else {
+        // Copying block to a new block with new blockId.
+        // Not truncating original block.
+        ReplicaBeingWritten newReplicaInfo = new ReplicaBeingWritten(
+            newBlockId, recoveryId, rur.getVolume(), blockFile.getParentFile(),
+            newlength);
+        newReplicaInfo.setNumBytes(newlength);
+        volumeMap.add(bpid, newReplicaInfo);
+        finalizeReplica(bpid, newReplicaInfo);
+      }
    }
 
     // finalize the block
     return finalizeReplica(bpid, rur);
   }
 
+  private File[] copyReplicaWithNewBlockIdAndGS(
+      ReplicaUnderRecovery replicaInfo, String bpid, long newBlkId, long newGS)
+      throws IOException {
+    String blockFileName = Block.BLOCK_FILE_PREFIX + newBlkId;
+    FsVolumeReference v = volumes.getNextVolume(
+        replicaInfo.getVolume().getStorageType(), replicaInfo.getNumBytes());
+    final File tmpDir = ((FsVolumeImpl) v.getVolume())
+        .getBlockPoolSlice(bpid).getTmpDir();
+    final File destDir = DatanodeUtil.idToBlockDir(tmpDir, newBlkId);
+    final File dstBlockFile = new File(destDir, blockFileName);
+    final File dstMetaFile = FsDatasetUtil.getMetaFile(dstBlockFile, newGS);
+    return copyBlockFiles(replicaInfo.getMetaFile(), replicaInfo.getBlockFile(),
+        dstMetaFile, dstBlockFile, true);
+  }
+
   @Override // FsDatasetSpi
   public synchronized long getReplicaVisibleLength(final ExtendedBlock block)
   throws IOException {

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirStatAndListingOp.java

@@ -424,7 +424,7 @@ class FSDirStatAndListingOp {
           fileNode.computeFileSizeNotIncludingLastUcBlock() : size;
 
       loc = fsd.getFSNamesystem().getBlockManager().createLocatedBlocks(
-          fileNode.getBlocks(), fileSize, isUc, 0L, size, false,
+          fileNode.getBlocks(snapshot), fileSize, isUc, 0L, size, false,
           inSnapshot, feInfo);
       if (loc == null) {
         loc = new LocatedBlocks();

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirectory.java

@@ -957,18 +957,31 @@ public class FSDirectory implements Closeable {
    * Unlike FSNamesystem.truncate, this will not schedule block recovery.
    */
   void unprotectedTruncate(String src, String clientName, String clientMachine,
-                           long newLength, long mtime)
+                           long newLength, long mtime, Block truncateBlock)
       throws UnresolvedLinkException, QuotaExceededException,
       SnapshotAccessControlException, IOException {
     INodesInPath iip = getINodesInPath(src, true);
+    INodeFile file = iip.getLastINode().asFile();
     BlocksMapUpdateInfo collectedBlocks = new BlocksMapUpdateInfo();
     boolean onBlockBoundary =
         unprotectedTruncate(iip, newLength, collectedBlocks, mtime);
 
     if(! onBlockBoundary) {
-      getFSNamesystem().prepareFileForWrite(src,
+      BlockInfo oldBlock = file.getLastBlock();
-          iip, clientName, clientMachine, false, false);
+      Block tBlk =
+      getFSNamesystem().prepareFileForTruncate(iip,
+          clientName, clientMachine, file.computeFileSize() - newLength,
+          truncateBlock);
+      assert Block.matchingIdAndGenStamp(tBlk, truncateBlock) &&
+          tBlk.getNumBytes() == truncateBlock.getNumBytes() :
+          "Should be the same block.";
+      if(oldBlock.getBlockId() != tBlk.getBlockId() &&
+         !file.isBlockInLatestSnapshot(oldBlock)) {
+        getBlockManager().removeBlockFromMap(oldBlock);
+      }
     }
+    assert onBlockBoundary == (truncateBlock == null) :
+      "truncateBlock is null iff on block boundary: " + truncateBlock;
     getFSNamesystem().removeBlocksAndUpdateSafemodeTotal(collectedBlocks);
   }
 
@@ -987,7 +1000,8 @@ public class FSDirectory implements Closeable {
   /**
    * Truncate has the following properties:
    * 1.) Any block deletions occur now.
-   * 2.) INode length is truncated now – clients can only read up to new length.
+   * 2.) INode length is truncated now – new clients can only read up to
+   * the truncated length.
    * 3.) INode will be set to UC and lastBlock set to UNDER_RECOVERY.
    * 4.) NN will trigger DN truncation recovery and waits for DNs to report.
    * 5.) File is considered UNDER_RECOVERY until truncation recovery completes.
@@ -1000,20 +1014,16 @@ public class FSDirectory implements Closeable {
                               long mtime) throws IOException {
     assert hasWriteLock();
     INodeFile file = iip.getLastINode().asFile();
+    int latestSnapshot = iip.getLatestSnapshotId();
+    file.recordModification(latestSnapshot, true);
     long oldDiskspace = file.diskspaceConsumed();
     long remainingLength =
         file.collectBlocksBeyondMax(newLength, collectedBlocks);
+    file.excludeSnapshotBlocks(latestSnapshot, collectedBlocks);
     file.setModificationTime(mtime);
     updateCount(iip, 0, file.diskspaceConsumed() - oldDiskspace, true);
-    // If on block boundary, then return
+    // return whether on a block boundary
-    long lastBlockDelta = remainingLength - newLength;
+    return (remainingLength - newLength) == 0;
-    if(lastBlockDelta == 0)
-      return true;
-    // Set new last block length
-    BlockInfo lastBlock = file.getLastBlock();
-    assert lastBlock.getNumBytes() - lastBlockDelta > 0 : "wrong block size";
-    lastBlock.setNumBytes(lastBlock.getNumBytes() - lastBlockDelta);
-    return false;
   }
 
   /**

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSEditLog.java

@@ -39,6 +39,7 @@ import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.fs.permission.PermissionStatus;
 import org.apache.hadoop.fs.XAttr;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
+import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.CacheDirectiveInfo;
 import org.apache.hadoop.hdfs.protocol.CachePoolInfo;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
@@ -902,13 +903,14 @@ public class FSEditLog implements LogsPurgeable {
    * Add truncate file record to edit log
    */
   void logTruncate(String src, String clientName, String clientMachine,
-                   long size, long timestamp) {
+                   long size, long timestamp, Block truncateBlock) {
     TruncateOp op = TruncateOp.getInstance(cache.get())
       .setPath(src)
       .setClientName(clientName)
       .setClientMachine(clientMachine)
       .setNewLength(size)
-      .setTimestamp(timestamp);
+      .setTimestamp(timestamp)
+      .setTruncateBlock(truncateBlock);
     logEdit(op);
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSEditLogLoader.java

@@ -861,7 +861,8 @@ public class FSEditLogLoader {
     case OP_TRUNCATE: {
       TruncateOp truncateOp = (TruncateOp) op;
       fsDir.unprotectedTruncate(truncateOp.src, truncateOp.clientName,
-          truncateOp.clientMachine, truncateOp.newLength, truncateOp.timestamp);
+          truncateOp.clientMachine, truncateOp.newLength, truncateOp.timestamp,
+          truncateOp.truncateBlock);
       break;
     }
     case OP_SET_STORAGE_POLICY: {

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSEditLogOp.java

@@ -2613,6 +2613,7 @@ public abstract class FSEditLogOp {
     String clientMachine;
     long newLength;
     long timestamp;
+    Block truncateBlock;
 
     private TruncateOp() {
       super(OP_TRUNCATE);
@@ -2656,6 +2657,11 @@ public abstract class FSEditLogOp {
       return this;
     }
 
+    TruncateOp setTruncateBlock(Block truncateBlock) {
+      this.truncateBlock = truncateBlock;
+      return this;
+    }
+
     @Override
     void readFields(DataInputStream in, int logVersion) throws IOException {
       src = FSImageSerialization.readString(in);
@@ -2663,6 +2669,10 @@ public abstract class FSEditLogOp {
       clientMachine = FSImageSerialization.readString(in);
       newLength = FSImageSerialization.readLong(in);
       timestamp = FSImageSerialization.readLong(in);
+      Block[] blocks =
+          FSImageSerialization.readCompactBlockArray(in, logVersion);
+      assert blocks.length <= 1 : "Truncate op should have 1 or 0 blocks";
+      truncateBlock = (blocks.length == 0) ? null : blocks[0];
     }
 
     @Override
@@ -2672,6 +2682,12 @@ public abstract class FSEditLogOp {
       FSImageSerialization.writeString(clientMachine, out);
       FSImageSerialization.writeLong(newLength, out);
       FSImageSerialization.writeLong(timestamp, out);
+      int size = truncateBlock != null ? 1 : 0;
+      Block[] blocks = new Block[size];
+      if (truncateBlock != null) {
+        blocks[0] = truncateBlock;
+      }
+      FSImageSerialization.writeCompactBlockArray(blocks, out);
     }
 
     @Override
@@ -2683,6 +2699,8 @@ public abstract class FSEditLogOp {
           Long.toString(newLength));
       XMLUtils.addSaxString(contentHandler, "TIMESTAMP",
           Long.toString(timestamp));
+      if(truncateBlock != null)
+        FSEditLogOp.blockToXml(contentHandler, truncateBlock);
     }
 
     @Override
@@ -2692,6 +2710,8 @@ public abstract class FSEditLogOp {
       this.clientMachine = st.getValue("CLIENTMACHINE");
       this.newLength = Long.parseLong(st.getValue("NEWLENGTH"));
       this.timestamp = Long.parseLong(st.getValue("TIMESTAMP"));
+      if (st.hasChildren("BLOCK"))
+        this.truncateBlock = FSEditLogOp.blockFromXml(st);
     }
 
     @Override
@@ -2707,6 +2727,8 @@ public abstract class FSEditLogOp {
       builder.append(newLength);
       builder.append(", timestamp=");
       builder.append(timestamp);
+      builder.append(", truncateBlock=");
+      builder.append(truncateBlock);
       builder.append(", opCode=");
       builder.append(opCode);
       builder.append(", txid=");

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -1800,8 +1800,8 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
             : dir.getFileEncryptionInfo(inode, iip.getPathSnapshotId(), iip);
 
     final LocatedBlocks blocks = blockManager.createLocatedBlocks(
-        inode.getBlocks(), fileSize, isUc, offset, length, needBlockToken,
+        inode.getBlocks(iip.getPathSnapshotId()), fileSize,
-        iip.isSnapshot(), feInfo);
+        isUc, offset, length, needBlockToken, iip.isSnapshot(), feInfo);
 
     // Set caching information for the located blocks.
     for (LocatedBlock lb : blocks.getLocatedBlocks()) {
@@ -1939,7 +1939,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
    * Truncation at block boundary is atomic, otherwise it requires
    * block recovery to truncate the last block of the file.
    *
-   * @return true if and client does not need to wait for block recovery,
+   * @return true if client does not need to wait for block recovery,
    * false if client needs to wait for block recovery.
    */
   boolean truncate(String src, long newLength,
@@ -2001,44 +2001,119 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       dir.checkPathAccess(pc, iip, FsAction.WRITE);
     }
     INodeFile file = iip.getLastINode().asFile();
-    // Data will be lost after truncate occurs so it cannot support snapshots.
-    if(file.isInLatestSnapshot(iip.getLatestSnapshotId()))
-      throw new HadoopIllegalArgumentException(
-          "Cannot truncate file with snapshot.");
     // Opening an existing file for write. May need lease recovery.
     recoverLeaseInternal(iip, src, clientName, clientMachine, false);
-    // Refresh INode as the file could have been closed
-    iip = dir.getINodesInPath4Write(src, true);
     file = INodeFile.valueOf(iip.getLastINode(), src);
     // Truncate length check.
     long oldLength = file.computeFileSize();
-    if(oldLength == newLength)
+    if(oldLength == newLength) {
       return true;
-    if(oldLength < newLength)
+    }
+    if(oldLength < newLength) {
       throw new HadoopIllegalArgumentException(
           "Cannot truncate to a larger file size. Current size: " + oldLength +
               ", truncate size: " + newLength + ".");
+    }
     // Perform INodeFile truncation.
     BlocksMapUpdateInfo collectedBlocks = new BlocksMapUpdateInfo();
     boolean onBlockBoundary = dir.truncate(iip, newLength,
                                            collectedBlocks, mtime);
-
+    Block truncateBlock = null;
     if(! onBlockBoundary) {
       // Open file for write, but don't log into edits
-      prepareFileForWrite(src, iip, clientName, clientMachine, false, false);
+      long lastBlockDelta = file.computeFileSize() - newLength;
-      file = INodeFile.valueOf(dir.getINode4Write(src), src);
+      assert lastBlockDelta > 0 : "delta is 0 only if on block bounday";
-      initializeBlockRecovery(file);
+      truncateBlock = prepareFileForTruncate(iip, clientName, clientMachine,
+          lastBlockDelta, null);
     }
-    getEditLog().logTruncate(src, clientName, clientMachine, newLength, mtime);
+    getEditLog().logTruncate(src, clientName, clientMachine, newLength, mtime,
+        truncateBlock);
     removeBlocks(collectedBlocks);
     return onBlockBoundary;
   }
 
-  void initializeBlockRecovery(INodeFile inodeFile) throws IOException {
+  /**
-    BlockInfo lastBlock = inodeFile.getLastBlock();
+   * Convert current INode to UnderConstruction.
-    long recoveryId = nextGenerationStamp(blockIdManager.isLegacyBlock(lastBlock));
+   * Recreate lease.
-    ((BlockInfoUnderConstruction)lastBlock).initializeBlockRecovery(
+   * Create new block for the truncated copy.
-        BlockUCState.BEING_TRUNCATED, recoveryId);
+   * Schedule truncation of the replicas.
+   *
+   * @return the returned block will be written to editLog and passed back into
+   * this method upon loading.
+   */
+  Block prepareFileForTruncate(INodesInPath iip,
+                               String leaseHolder,
+                               String clientMachine,
+                               long lastBlockDelta,
+                               Block newBlock)
+      throws IOException {
+    INodeFile file = iip.getLastINode().asFile();
+    String src = iip.getPath();
+    file.recordModification(iip.getLatestSnapshotId());
+    file.toUnderConstruction(leaseHolder, clientMachine);
+    assert file.isUnderConstruction() : "inode should be under construction.";
+    leaseManager.addLease(
+        file.getFileUnderConstructionFeature().getClientName(), src);
+    boolean shouldRecoverNow = (newBlock == null);
+    BlockInfo oldBlock = file.getLastBlock();
+    boolean shouldCopyOnTruncate = shouldCopyOnTruncate(file, oldBlock);
+    if(newBlock == null) {
+      newBlock = (shouldCopyOnTruncate) ? createNewBlock() :
+          new Block(oldBlock.getBlockId(), oldBlock.getNumBytes(),
+              nextGenerationStamp(blockIdManager.isLegacyBlock(oldBlock)));
+    }
+
+    BlockInfoUnderConstruction truncatedBlockUC;
+    if(shouldCopyOnTruncate) {
+      // Add new truncateBlock into blocksMap and
+      // use oldBlock as a source for copy-on-truncate recovery
+      truncatedBlockUC = new BlockInfoUnderConstruction(newBlock,
+          file.getBlockReplication());
+      truncatedBlockUC.setNumBytes(oldBlock.getNumBytes() - lastBlockDelta);
+      truncatedBlockUC.setTruncateBlock(oldBlock);
+      file.setLastBlock(truncatedBlockUC, blockManager.getStorages(oldBlock));
+      getBlockManager().addBlockCollection(truncatedBlockUC, file);
+
+      NameNode.stateChangeLog.info("BLOCK* prepareFileForTruncate: "
+          + "Scheduling copy-on-truncate to new size "
+          + truncatedBlockUC.getNumBytes() + " new block " + newBlock
+          + " old block " + truncatedBlockUC.getTruncateBlock());
+    } else {
+      // Use new generation stamp for in-place truncate recovery
+      blockManager.convertLastBlockToUnderConstruction(file, lastBlockDelta);
+      oldBlock = file.getLastBlock();
+      assert !oldBlock.isComplete() : "oldBlock should be under construction";
+      truncatedBlockUC = (BlockInfoUnderConstruction) oldBlock;
+      truncatedBlockUC.setTruncateBlock(new Block(oldBlock));
+      truncatedBlockUC.getTruncateBlock().setNumBytes(
+          oldBlock.getNumBytes() - lastBlockDelta);
+      truncatedBlockUC.getTruncateBlock().setGenerationStamp(
+          newBlock.getGenerationStamp());
+
+      NameNode.stateChangeLog.debug("BLOCK* prepareFileForTruncate: "
+          + "Scheduling in-place block truncate to new size "
+          + truncatedBlockUC.getTruncateBlock().getNumBytes()
+          + " block=" + truncatedBlockUC);
+    }
+    if(shouldRecoverNow)
+      truncatedBlockUC.initializeBlockRecovery(newBlock.getGenerationStamp());
+
+    // update the quota: use the preferred block size for UC block
+    final long diff =
+        file.getPreferredBlockSize() - truncatedBlockUC.getNumBytes();
+    dir.updateSpaceConsumed(iip, 0, diff * file.getBlockReplication());
+    return newBlock;
+  }
+
+  /**
+   * Defines if a replica needs to be copied on truncate or
+   * can be truncated in place.
+   */
+  boolean shouldCopyOnTruncate(INodeFile file, BlockInfo blk) {
+    if(!isUpgradeFinalized()) {
+      return true;
+    }
+    return file.isBlockInLatestSnapshot(blk);
   }
 
   /**
@@ -2565,7 +2640,8 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
     leaseManager.addLease(
         file.getFileUnderConstructionFeature().getClientName(), src);
     
-    LocatedBlock ret = blockManager.convertLastBlockToUnderConstruction(file);
+    LocatedBlock ret =
+        blockManager.convertLastBlockToUnderConstruction(file, 0);
     if (ret != null) {
       // update the quota: use the preferred block size for UC block
       final long diff = file.getPreferredBlockSize() - ret.getBlockSize();
@@ -2628,7 +2704,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
     return false;
   }
 
-  private void recoverLeaseInternal(INodesInPath iip,
+  void recoverLeaseInternal(INodesInPath iip,
       String src, String holder, String clientMachine, boolean force)
       throws IOException {
     assert hasWriteLock();
@@ -2690,8 +2766,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
         } else {
           final BlockInfo lastBlock = file.getLastBlock();
           if (lastBlock != null
-              && (lastBlock.getBlockUCState() == BlockUCState.UNDER_RECOVERY ||
+              && lastBlock.getBlockUCState() == BlockUCState.UNDER_RECOVERY) {
-                 lastBlock.getBlockUCState() == BlockUCState.BEING_TRUNCATED)) {
             throw new RecoveryInProgressException("Recovery in progress, file ["
                 + src + "], " + "lease owner [" + lease.getHolder() + "]");
           } else {
@@ -3845,8 +3920,18 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       throw new AlreadyBeingCreatedException(message);
     case UNDER_CONSTRUCTION:
     case UNDER_RECOVERY:
-    case BEING_TRUNCATED:
       final BlockInfoUnderConstruction uc = (BlockInfoUnderConstruction)lastBlock;
+      // determine if last block was intended to be truncated
+      Block recoveryBlock = uc.getTruncateBlock();
+      boolean truncateRecovery = recoveryBlock != null;
+      boolean copyOnTruncate = truncateRecovery &&
+          recoveryBlock.getBlockId() != uc.getBlockId();
+      assert !copyOnTruncate ||
+          recoveryBlock.getBlockId() < uc.getBlockId() &&
+          recoveryBlock.getGenerationStamp() < uc.getGenerationStamp() &&
+          recoveryBlock.getNumBytes() > uc.getNumBytes() :
+            "wrong recoveryBlock";
+
       // setup the last block locations from the blockManager if not known
       if (uc.getNumExpectedLocations() == 0) {
         uc.setExpectedLocations(blockManager.getStorages(lastBlock));
@@ -3867,9 +3952,12 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       // start recovery of the last block for this file
       long blockRecoveryId = nextGenerationStamp(blockIdManager.isLegacyBlock(uc));
       lease = reassignLease(lease, src, recoveryLeaseHolder, pendingFile);
-      if (uc.getBlockUCState() != BlockUCState.BEING_TRUNCATED) {
+      if(copyOnTruncate) {
-        uc.initializeBlockRecovery(blockRecoveryId);
+        uc.setGenerationStamp(blockRecoveryId);
+      } else if(truncateRecovery) {
+        recoveryBlock.setGenerationStamp(blockRecoveryId);
       }
+      uc.initializeBlockRecovery(blockRecoveryId);
       leaseManager.renewLease(lease);
       // Cannot close file right now, since the last block requires recovery.
       // This may potentially cause infinite loop in lease recovery
@@ -3979,11 +4067,11 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
     return true;
   }
 
-  void commitBlockSynchronization(ExtendedBlock lastblock,
+  void commitBlockSynchronization(ExtendedBlock oldBlock,
       long newgenerationstamp, long newlength,
       boolean closeFile, boolean deleteblock, DatanodeID[] newtargets,
       String[] newtargetstorages) throws IOException {
-    LOG.info("commitBlockSynchronization(lastblock=" + lastblock
+    LOG.info("commitBlockSynchronization(oldBlock=" + oldBlock
              + ", newgenerationstamp=" + newgenerationstamp
              + ", newlength=" + newlength
              + ", newtargets=" + Arrays.asList(newtargets)
@@ -4002,17 +4090,17 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       checkNameNodeSafeMode(
           "Cannot commitBlockSynchronization while in safe mode");
       final BlockInfo storedBlock = getStoredBlock(
-          ExtendedBlock.getLocalBlock(lastblock));
+          ExtendedBlock.getLocalBlock(oldBlock));
       if (storedBlock == null) {
         if (deleteblock) {
           // This may be a retry attempt so ignore the failure
           // to locate the block.
           if (LOG.isDebugEnabled()) {
-            LOG.debug("Block (=" + lastblock + ") not found");
+            LOG.debug("Block (=" + oldBlock + ") not found");
           }
           return;
         } else {
-          throw new IOException("Block (=" + lastblock + ") not found");
+          throw new IOException("Block (=" + oldBlock + ") not found");
         }
       }
       //
@@ -4039,34 +4127,40 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
             + iFile.getFullPathName() + ", likely due to delayed block"
             + " removal");
       }
-      if (!iFile.isUnderConstruction() || storedBlock.isComplete()) {
+      if ((!iFile.isUnderConstruction() || storedBlock.isComplete()) &&
+          iFile.getLastBlock().isComplete()) {
         if (LOG.isDebugEnabled()) {
-          LOG.debug("Unexpected block (=" + lastblock
+          LOG.debug("Unexpected block (=" + oldBlock
                     + ") since the file (=" + iFile.getLocalName()
                     + ") is not under construction");
         }
         return;
       }
 
-      long recoveryId =
+      BlockInfoUnderConstruction truncatedBlock =
-        ((BlockInfoUnderConstruction)storedBlock).getBlockRecoveryId();
+          (BlockInfoUnderConstruction) iFile.getLastBlock();
+      long recoveryId = truncatedBlock.getBlockRecoveryId();
+      boolean copyTruncate =
+          truncatedBlock.getBlockId() != storedBlock.getBlockId();
       if(recoveryId != newgenerationstamp) {
         throw new IOException("The recovery id " + newgenerationstamp
                               + " does not match current recovery id "
-                              + recoveryId + " for block " + lastblock); 
+                              + recoveryId + " for block " + oldBlock);
       }
 
       if (deleteblock) {
-        Block blockToDel = ExtendedBlock.getLocalBlock(lastblock);
+        Block blockToDel = ExtendedBlock.getLocalBlock(oldBlock);
         boolean remove = iFile.removeLastBlock(blockToDel);
         if (remove) {
-          blockManager.removeBlockFromMap(storedBlock);
+          blockManager.removeBlock(storedBlock);
         }
       }
       else {
         // update last block
-        storedBlock.setGenerationStamp(newgenerationstamp);
+        if(!copyTruncate) {
-        storedBlock.setNumBytes(newlength);
+          storedBlock.setGenerationStamp(newgenerationstamp);
+          storedBlock.setNumBytes(newlength);
+        }
 
         // find the DatanodeDescriptor objects
         // There should be no locations in the blockManager till now because the
@@ -4096,7 +4190,11 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
             DatanodeStorageInfo storageInfo =
                 trimmedTargets.get(i).getStorageInfo(trimmedStorages.get(i));
             if (storageInfo != null) {
-              storageInfo.addBlock(storedBlock);
+              if(copyTruncate) {
+                storageInfo.addBlock(truncatedBlock);
+              } else {
+                storageInfo.addBlock(storedBlock);
+              }
             }
           }
         }
@@ -4106,11 +4204,22 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
             blockManager.getDatanodeManager().getDatanodeStorageInfos(
                 trimmedTargets.toArray(new DatanodeID[trimmedTargets.size()]),
                 trimmedStorages.toArray(new String[trimmedStorages.size()]));
-        iFile.setLastBlock(storedBlock, trimmedStorageInfos);
+        if(copyTruncate) {
+          iFile.setLastBlock(truncatedBlock, trimmedStorageInfos);
+        } else {
+          iFile.setLastBlock(storedBlock, trimmedStorageInfos);
+        }
       }
 
       if (closeFile) {
-        src = closeFileCommitBlocks(iFile, storedBlock);
+        if(copyTruncate) {
+          src = closeFileCommitBlocks(iFile, truncatedBlock);
+          if(!iFile.isBlockInLatestSnapshot(storedBlock)) {
+            blockManager.removeBlock(storedBlock);
+          }
+        } else {
+          src = closeFileCommitBlocks(iFile, storedBlock);
+        }
       } else {
         // If this commit does not want to close the file, persist blocks
         src = iFile.getFullPathName();
@@ -4121,13 +4230,13 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
     }
     getEditLog().logSync();
     if (closeFile) {
-      LOG.info("commitBlockSynchronization(newblock=" + lastblock
+      LOG.info("commitBlockSynchronization(oldBlock=" + oldBlock
           + ", file=" + src
           + ", newgenerationstamp=" + newgenerationstamp
           + ", newlength=" + newlength
           + ", newtargets=" + Arrays.asList(newtargets) + ") successful");
     } else {
-      LOG.info("commitBlockSynchronization(" + lastblock + ") successful");
+      LOG.info("commitBlockSynchronization(" + oldBlock + ") successful");
     }
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INode.java

@@ -228,7 +228,8 @@ public abstract class INode implements INodeAttributes, Diff.Element<byte[]> {
 
   /** Is this inode in the latest snapshot? */
   public final boolean isInLatestSnapshot(final int latestSnapshotId) {
-    if (latestSnapshotId == Snapshot.CURRENT_STATE_ID) {
+    if (latestSnapshotId == Snapshot.CURRENT_STATE_ID ||
+        latestSnapshotId == Snapshot.NO_SNAPSHOT_ID) {
       return false;
     }
     // if parent is a reference node, parent must be a renamed node. We can 
@@ -817,9 +818,13 @@ public abstract class INode implements INodeAttributes, Diff.Element<byte[]> {
      * @param toDelete the to-be-deleted block
      */
     public void addDeleteBlock(Block toDelete) {
-      if (toDelete != null) {
+      assert toDelete != null : "toDelete is null";
-        toDeleteList.add(toDelete);
+      toDeleteList.add(toDelete);
-      }
+    }
+
+    public void removeDeleteBlock(Block block) {
+      assert block != null : "block is null";
+      toDeleteList.remove(block);
     }
 
     /**

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeFile.java

@@ -24,7 +24,9 @@ import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.Arrays;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.permission.PermissionStatus;
@@ -304,6 +306,11 @@ public class INodeFile extends INodeWithAdditionalFields
   @Override
   public void recordModification(final int latestSnapshotId)
       throws QuotaExceededException {
+    recordModification(latestSnapshotId, false);
+  }
+
+  public void recordModification(final int latestSnapshotId, boolean withBlocks)
+      throws QuotaExceededException {
     if (isInLatestSnapshot(latestSnapshotId)
         && !shouldRecordInSrcSnapshot(latestSnapshotId)) {
       // the file is in snapshot, create a snapshot feature if it does not have
@@ -312,7 +319,7 @@ public class INodeFile extends INodeWithAdditionalFields
         sf = addSnapshotFeature(null);
       }
       // record self in the diff list if necessary
-      sf.getDiffs().saveSelf2Snapshot(latestSnapshotId, this, null);
+      sf.getDiffs().saveSelf2Snapshot(latestSnapshotId, this, null, withBlocks);
     }
   }
 
@@ -415,6 +422,20 @@ public class INodeFile extends INodeWithAdditionalFields
     return this.blocks;
   }
 
+  /** @return blocks of the file corresponding to the snapshot. */
+  public BlockInfo[] getBlocks(int snapshot) {
+    if(snapshot == CURRENT_STATE_ID || getDiffs() == null)
+      return getBlocks();
+    FileDiff diff = getDiffs().getDiffById(snapshot);
+    BlockInfo[] snapshotBlocks = diff == null ? getBlocks() : diff.getBlocks();
+    if(snapshotBlocks != null)
+      return snapshotBlocks;
+    // Blocks are not in the current snapshot
+    // Find next snapshot with blocks present or return current file blocks
+    snapshotBlocks = getDiffs().findLaterSnapshotBlocks(diff.getSnapshotId());
+    return (snapshotBlocks == null) ? getBlocks() : snapshotBlocks;
+  }
+
   void updateBlockCollection() {
     if (blocks != null) {
       for(BlockInfo b : blocks) {
@@ -509,9 +530,9 @@ public class INodeFile extends INodeWithAdditionalFields
     }
     clear();
     removedINodes.add(this);
-    
     FileWithSnapshotFeature sf = getFileWithSnapshotFeature();
     if (sf != null) {
+      sf.getDiffs().destroyAndCollectSnapshotBlocks(collectedBlocks);
       sf.clearDiffs();
     }
   }
@@ -554,39 +575,23 @@ public class INodeFile extends INodeWithAdditionalFields
   @Override
   public final ContentSummaryComputationContext computeContentSummary(
       final ContentSummaryComputationContext summary) {
-    computeContentSummary4Snapshot(summary.getCounts());
+    final Content.Counts counts = summary.getCounts();
-    computeContentSummary4Current(summary.getCounts());
-    return summary;
-  }
-
-  private void computeContentSummary4Snapshot(final Content.Counts counts) {
-    // file length and diskspace only counted for the latest state of the file
-    // i.e. either the current state or the last snapshot
     FileWithSnapshotFeature sf = getFileWithSnapshotFeature();
-    if (sf != null) {
+    if (sf == null) {
+      counts.add(Content.LENGTH, computeFileSize());
+      counts.add(Content.FILE, 1);
+    } else {
       final FileDiffList diffs = sf.getDiffs();
       final int n = diffs.asList().size();
       counts.add(Content.FILE, n);
       if (n > 0 && sf.isCurrentFileDeleted()) {
         counts.add(Content.LENGTH, diffs.getLast().getFileSize());
-      }
+      } else {
-
+        counts.add(Content.LENGTH, computeFileSize());
-      if (sf.isCurrentFileDeleted()) {
-        final long lastFileSize = diffs.getLast().getFileSize();
-        counts.add(Content.DISKSPACE, lastFileSize * getBlockReplication());
       }
     }
-  }
-
-  private void computeContentSummary4Current(final Content.Counts counts) {
-    FileWithSnapshotFeature sf = this.getFileWithSnapshotFeature();
-    if (sf != null && sf.isCurrentFileDeleted()) {
-      return;
-    }
-
-    counts.add(Content.LENGTH, computeFileSize());
-    counts.add(Content.FILE, 1);
     counts.add(Content.DISKSPACE, diskspaceConsumed());
+    return summary;
   }
 
   /** The same as computeFileSize(null). */
@@ -651,9 +656,36 @@ public class INodeFile extends INodeWithAdditionalFields
     return size;
   }
 
+  /**
+   * Compute size consumed by all blocks of the current file,
+   * including blocks in its snapshots.
+   * Use preferred block size for the last block if it is under construction.
+   */
   public final long diskspaceConsumed() {
-    // use preferred block size for the last block if it is under construction
+    FileWithSnapshotFeature sf = getFileWithSnapshotFeature();
-    return computeFileSize(true, true) * getBlockReplication();
+    if(sf == null) {
+      return computeFileSize(true, true) * getBlockReplication();
+    }
+
+    // Collect all distinct blocks
+    long size = 0;
+    Set<Block> allBlocks = new HashSet<Block>(Arrays.asList(getBlocks()));
+    List<FileDiff> diffs = sf.getDiffs().asList();
+    for(FileDiff diff : diffs) {
+      BlockInfo[] diffBlocks = diff.getBlocks();
+      if (diffBlocks != null) {
+        allBlocks.addAll(Arrays.asList(diffBlocks));
+      }
+    }
+    for(Block block : allBlocks) {
+      size += block.getNumBytes();
+    }
+    // check if the last block is under construction
+    BlockInfo lastBlock = getLastBlock();
+    if(lastBlock != null && lastBlock instanceof BlockInfoUnderConstruction) {
+      size += getPreferredBlockSize() - lastBlock.getNumBytes();
+    }
+    return size * getBlockReplication();
   }
 
   public final long diskspaceConsumed(int lastSnapshotId) {
@@ -706,7 +738,7 @@ public class INodeFile extends INodeWithAdditionalFields
     final BlockInfo[] oldBlocks = getBlocks();
     if (oldBlocks == null)
       return 0;
-    //find the minimum n such that the size of the first n blocks > max
+    // find the minimum n such that the size of the first n blocks > max
     int n = 0;
     long size = 0;
     for(; n < oldBlocks.length && max > size; n++) {
@@ -717,15 +749,7 @@ public class INodeFile extends INodeWithAdditionalFields
 
     // starting from block n, the data is beyond max.
     // resize the array.
-    final BlockInfo[] newBlocks;
+    truncateBlocksTo(n);
-    if (n == 0) {
-      newBlocks = BlockInfo.EMPTY_ARRAY;
-    } else {
-      newBlocks = new BlockInfo[n];
-      System.arraycopy(oldBlocks, 0, newBlocks, 0, n);
-    }
-    // set new blocks
-    setBlocks(newBlocks);
 
     // collect the blocks beyond max
     if (collectedBlocks != null) {
@@ -735,4 +759,67 @@ public class INodeFile extends INodeWithAdditionalFields
     }
     return size;
   }
+
+  void truncateBlocksTo(int n) {
+    final BlockInfo[] newBlocks;
+    if (n == 0) {
+      newBlocks = BlockInfo.EMPTY_ARRAY;
+    } else {
+      newBlocks = new BlockInfo[n];
+      System.arraycopy(getBlocks(), 0, newBlocks, 0, n);
+    }
+    // set new blocks
+    setBlocks(newBlocks);
+  }
+
+  public void collectBlocksBeyondSnapshot(BlockInfo[] snapshotBlocks,
+                                          BlocksMapUpdateInfo collectedBlocks) {
+    BlockInfo[] oldBlocks = getBlocks();
+    if(snapshotBlocks == null || oldBlocks == null)
+      return;
+    // Skip blocks in common between the file and the snapshot
+    int n = 0;
+    while(n < oldBlocks.length && n < snapshotBlocks.length &&
+          oldBlocks[n] == snapshotBlocks[n]) {
+      n++;
+    }
+    truncateBlocksTo(n);
+    // Collect the remaining blocks of the file
+    while(n < oldBlocks.length) {
+      collectedBlocks.addDeleteBlock(oldBlocks[n++]);
+    }
+  }
+
+  /** Exclude blocks collected for deletion that belong to a snapshot. */
+  void excludeSnapshotBlocks(int snapshotId,
+                             BlocksMapUpdateInfo collectedBlocks) {
+    if(collectedBlocks == null || collectedBlocks.getToDeleteList().isEmpty())
+      return;
+    FileWithSnapshotFeature sf = getFileWithSnapshotFeature();
+    if(sf == null)
+      return;
+    BlockInfo[] snapshotBlocks = 
+        getDiffs().findEarlierSnapshotBlocks(snapshotId);
+    if(snapshotBlocks == null)
+      return;
+    List<Block> toDelete = collectedBlocks.getToDeleteList();
+    for(Block blk : snapshotBlocks) {
+      if(toDelete.contains(blk))
+        collectedBlocks.removeDeleteBlock(blk);
+    }
+  }
+
+  /**
+   * @return true if the block is contained in a snapshot or false otherwise.
+   */
+  boolean isBlockInLatestSnapshot(BlockInfo block) {
+    FileWithSnapshotFeature sf = this.getFileWithSnapshotFeature();
+    if (sf == null || sf.getDiffs() == null)
+      return false;
+    BlockInfo[] snapshotBlocks =
+        getDiffs().findEarlierSnapshotBlocks(getDiffs().getLastSnapshotId());
+    if(snapshotBlocks == null)
+      return false;
+    return Arrays.asList(snapshotBlocks).contains(block);
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeLayoutVersion.java

@@ -69,7 +69,8 @@ public class NameNodeLayoutVersion {
     CREATE_OVERWRITE(-58, "Use single editlog record for " +
       "creating file with overwrite"),
     XATTRS_NAMESPACE_EXT(-59, "Increase number of xattr namespaces"),
-    BLOCK_STORAGE_POLICY(-60, "Block Storage policy");
+    BLOCK_STORAGE_POLICY(-60, "Block Storage policy"),
+    TRUNCATE(-61, "Truncate");
 
     private final FeatureInfo info;
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/AbstractINodeDiffList.java

@@ -163,9 +163,12 @@ abstract class AbstractINodeDiffList<N extends INode,
    *                  id, otherwise <=.
    * @return The id of the latest snapshot before the given snapshot.
    */
-  private final int getPrior(int anchorId, boolean exclusive) {
+  public final int getPrior(int anchorId, boolean exclusive) {
     if (anchorId == Snapshot.CURRENT_STATE_ID) {
-      return getLastSnapshotId();
+      int last = getLastSnapshotId();
+      if(exclusive && last == anchorId)
+        return Snapshot.NO_SNAPSHOT_ID;
+      return last;
     }
     final int i = Collections.binarySearch(diffs, anchorId);
     if (exclusive) { // must be the one before
@@ -290,10 +293,11 @@ abstract class AbstractINodeDiffList<N extends INode,
   }
 
   /** Save the snapshot copy to the latest snapshot. */
-  public void saveSelf2Snapshot(int latestSnapshotId, N currentINode,
+  public D saveSelf2Snapshot(int latestSnapshotId, N currentINode,
       A snapshotCopy) throws QuotaExceededException {
+    D diff = null;
     if (latestSnapshotId != Snapshot.CURRENT_STATE_ID) {
-      D diff = checkAndAddLatestSnapshotDiff(latestSnapshotId, currentINode);
+      diff = checkAndAddLatestSnapshotDiff(latestSnapshotId, currentINode);
       if (diff.snapshotINode == null) {
         if (snapshotCopy == null) {
           snapshotCopy = createSnapshotCopy(currentINode);
@@ -301,6 +305,7 @@ abstract class AbstractINodeDiffList<N extends INode,
         diff.saveSnapshotCopy(snapshotCopy);
       }
     }
+    return diff;
   }
   
   @Override

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/FSImageFormatPBSnapshot.java

@@ -36,6 +36,10 @@ import java.util.Map;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.permission.PermissionStatus;
+import org.apache.hadoop.hdfs.protocol.Block;
+import org.apache.hadoop.hdfs.protocol.proto.HdfsProtos.BlockProto;
+import org.apache.hadoop.hdfs.protocolPB.PBHelper;
+import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
 import org.apache.hadoop.hdfs.server.namenode.AclEntryStatusFormat;
 import org.apache.hadoop.hdfs.server.namenode.AclFeature;
 import org.apache.hadoop.hdfs.server.namenode.FSDirectory;
@@ -230,6 +234,20 @@ public class FSImageFormatPBSnapshot {
 
         FileDiff diff = new FileDiff(pbf.getSnapshotId(), copy, null,
             pbf.getFileSize());
+        List<BlockProto> bpl = pbf.getBlocksList();
+        BlockInfo[] blocks = new BlockInfo[bpl.size()];
+        for(int j = 0, e = bpl.size(); j < e; ++j) {
+          Block blk = PBHelper.convert(bpl.get(j));
+          BlockInfo storedBlock =  fsn.getBlockManager().getStoredBlock(blk);
+          if(storedBlock == null) {
+            storedBlock = fsn.getBlockManager().addBlockCollection(
+                new BlockInfo(blk, copy.getFileReplication()), file);
+          }
+          blocks[j] = storedBlock;
+        }
+        if(blocks.length > 0) {
+          diff.setBlocks(blocks);
+        }
         diffs.addFirst(diff);
       }
       file.addSnapshotFeature(diffs);
@@ -473,6 +491,11 @@ public class FSImageFormatPBSnapshot {
           SnapshotDiffSection.FileDiff.Builder fb = SnapshotDiffSection.FileDiff
               .newBuilder().setSnapshotId(diff.getSnapshotId())
               .setFileSize(diff.getFileSize());
+          if(diff.getBlocks() != null) {
+            for(Block block : diff.getBlocks()) {
+              fb.addBlocks(PBHelper.convert(block));
+            }
+          }
           INodeFileAttributes copy = diff.snapshotINode;
           if (copy != null) {
             fb.setName(ByteString.copyFrom(copy.getLocalNameBytes()))

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/FileDiff.java

@@ -19,8 +19,10 @@ package org.apache.hadoop.hdfs.server.namenode.snapshot;
 
 import java.io.DataOutput;
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.List;
 
+import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
 import org.apache.hadoop.hdfs.server.namenode.FSImageSerialization;
 import org.apache.hadoop.hdfs.server.namenode.INode;
 import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
@@ -37,10 +39,13 @@ public class FileDiff extends
 
   /** The file size at snapshot creation time. */
   private final long fileSize;
+  /** A copy of the INodeFile block list. Used in truncate. */
+  private BlockInfo[] blocks;
 
   FileDiff(int snapshotId, INodeFile file) {
     super(snapshotId, null, null);
     fileSize = file.computeFileSize();
+    blocks = null;
   }
 
   /** Constructor used by FSImage loading */
@@ -48,6 +53,7 @@ public class FileDiff extends
       FileDiff posteriorDiff, long fileSize) {
     super(snapshotId, snapshotINode, posteriorDiff);
     this.fileSize = fileSize;
+    blocks = null;
   }
 
   /** @return the file size in the snapshot. */
@@ -55,13 +61,32 @@ public class FileDiff extends
     return fileSize;
   }
 
+  /**
+   * Copy block references into the snapshot
+   * up to the current {@link #fileSize}.
+   * Should be done only once.
+   */
+  public void setBlocks(BlockInfo[] blocks) {
+    if(this.blocks != null)
+      return;
+    int numBlocks = 0;
+    for(long s = 0; numBlocks < blocks.length && s < fileSize; numBlocks++)
+      s += blocks[numBlocks].getNumBytes();
+    this.blocks = Arrays.copyOf(blocks, numBlocks);
+  }
+
+  public BlockInfo[] getBlocks() {
+    return blocks;
+  }
+
   @Override
   Quota.Counts combinePosteriorAndCollectBlocks(INodeFile currentINode,
       FileDiff posterior, BlocksMapUpdateInfo collectedBlocks,
       final List<INode> removedINodes) {
-    return currentINode.getFileWithSnapshotFeature()
+    FileWithSnapshotFeature sf = currentINode.getFileWithSnapshotFeature();
-        .updateQuotaAndCollectBlocks(currentINode, posterior, collectedBlocks,
+    assert sf != null : "FileWithSnapshotFeature is null";
-            removedINodes);
+    return sf.updateQuotaAndCollectBlocks(
+        currentINode, posterior, collectedBlocks, removedINodes);
   }
   
   @Override
@@ -91,4 +116,13 @@ public class FileDiff extends
         .updateQuotaAndCollectBlocks(currentINode, this, collectedBlocks,
             removedINodes);
   }
+
+  public void destroyAndCollectSnapshotBlocks(
+      BlocksMapUpdateInfo collectedBlocks) {
+    if(blocks == null || collectedBlocks == null)
+      return;
+    for(BlockInfo blk : blocks)
+      collectedBlocks.addDeleteBlock(blk);
+    blocks = null;
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/FileDiffList.java

@@ -17,6 +17,13 @@
  */
 package org.apache.hadoop.hdfs.server.namenode.snapshot;
 
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.hadoop.hdfs.protocol.QuotaExceededException;
+import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
+import org.apache.hadoop.hdfs.server.namenode.INode;
+import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
 import org.apache.hadoop.hdfs.server.namenode.INodeFile;
 import org.apache.hadoop.hdfs.server.namenode.INodeFileAttributes;
 
@@ -33,4 +40,95 @@ public class FileDiffList extends
   INodeFileAttributes createSnapshotCopy(INodeFile currentINode) {
     return new INodeFileAttributes.SnapshotCopy(currentINode);
   }
+
+  public void destroyAndCollectSnapshotBlocks(
+      BlocksMapUpdateInfo collectedBlocks) {
+    for(FileDiff d : asList())
+      d.destroyAndCollectSnapshotBlocks(collectedBlocks);
+  }
+
+  public void saveSelf2Snapshot(int latestSnapshotId, INodeFile iNodeFile,
+      INodeFileAttributes snapshotCopy, boolean withBlocks)
+          throws QuotaExceededException {
+    final FileDiff diff =
+        super.saveSelf2Snapshot(latestSnapshotId, iNodeFile, snapshotCopy);
+    if(withBlocks)  // Store blocks if this is the first update
+      diff.setBlocks(iNodeFile.getBlocks());
+  }
+
+  public BlockInfo[] findEarlierSnapshotBlocks(int snapshotId) {
+    assert snapshotId != Snapshot.NO_SNAPSHOT_ID : "Wrong snapshot id";
+    if(snapshotId == Snapshot.CURRENT_STATE_ID) {
+      return null;
+    }
+    List<FileDiff> diffs = this.asList();
+    int i = Collections.binarySearch(diffs, snapshotId);
+    BlockInfo[] blocks = null;
+    for(i = i >= 0 ? i : -i; i < diffs.size(); i--) {
+      blocks = diffs.get(i).getBlocks();
+      if(blocks != null) {
+        break;
+      }
+    }
+    return blocks;
+  }
+
+  public BlockInfo[] findLaterSnapshotBlocks(int snapshotId) {
+    assert snapshotId != Snapshot.NO_SNAPSHOT_ID : "Wrong snapshot id";
+    if(snapshotId == Snapshot.CURRENT_STATE_ID) {
+      return null;
+    }
+    List<FileDiff> diffs = this.asList();
+    int i = Collections.binarySearch(diffs, snapshotId);
+    BlockInfo[] blocks = null;
+    for(i = i >= 0 ? i+1 : -i-1; i < diffs.size(); i++) {
+      blocks = diffs.get(i).getBlocks();
+      if(blocks != null) {
+        break;
+      }
+    }
+    return blocks;
+  }
+
+  /**
+   * Copy blocks from the removed snapshot into the previous snapshot
+   * up to the file length of the latter.
+   * Collect unused blocks of the removed snapshot.
+   */
+  void combineAndCollectSnapshotBlocks(INodeFile file,
+                                       FileDiff removed,
+                                       BlocksMapUpdateInfo collectedBlocks,
+                                       List<INode> removedINodes) {
+    BlockInfo[] removedBlocks = removed.getBlocks();
+    if(removedBlocks == null) {
+      FileWithSnapshotFeature sf = file.getFileWithSnapshotFeature();
+      assert sf != null : "FileWithSnapshotFeature is null";
+      if(sf.isCurrentFileDeleted())
+        sf.collectBlocksAndClear(file, collectedBlocks, removedINodes);
+      return;
+    }
+    int p = getPrior(removed.getSnapshotId(), true);
+    FileDiff earlierDiff = p == Snapshot.NO_SNAPSHOT_ID ? null : getDiffById(p);
+    // Copy blocks to the previous snapshot if not set already
+    if(earlierDiff != null)
+      earlierDiff.setBlocks(removedBlocks);
+    BlockInfo[] earlierBlocks =
+        (earlierDiff == null ? new BlockInfo[]{} : earlierDiff.getBlocks());
+    // Find later snapshot (or file itself) with blocks
+    BlockInfo[] laterBlocks = findLaterSnapshotBlocks(removed.getSnapshotId());
+    laterBlocks = (laterBlocks==null) ? file.getBlocks() : laterBlocks;
+    // Skip blocks, which belong to either the earlier or the later lists
+    int i = 0;
+    for(; i < removedBlocks.length; i++) {
+      if(i < earlierBlocks.length && removedBlocks[i] == earlierBlocks[i])
+        continue;
+      if(i < laterBlocks.length && removedBlocks[i] == laterBlocks[i])
+        continue;
+      break;
+    }
+    // Collect the remaining blocks of the file
+    while(i < removedBlocks.length) {
+      collectedBlocks.addDeleteBlock(removedBlocks[i++]);
+    }
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/FileWithSnapshotFeature.java

@@ -21,6 +21,7 @@ import java.util.List;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.hdfs.protocol.QuotaExceededException;
+import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
 import org.apache.hadoop.hdfs.server.namenode.AclFeature;
 import org.apache.hadoop.hdfs.server.namenode.INode;
 import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
@@ -155,7 +156,8 @@ public class FileWithSnapshotFeature implements INode.Feature {
       }
     }
 
-    collectBlocksAndClear(file, collectedBlocks, removedINodes);
+    getDiffs().combineAndCollectSnapshotBlocks(
+        file, removed, collectedBlocks, removedINodes);
 
     long dsDelta = oldDiskspace - file.diskspaceConsumed();
     return Quota.Counts.newInstance(0, dsDelta);
@@ -165,7 +167,7 @@ public class FileWithSnapshotFeature implements INode.Feature {
    * If some blocks at the end of the block list no longer belongs to
    * any inode, collect them and update the block list.
    */
-  private void collectBlocksAndClear(final INodeFile file,
+  public void collectBlocksAndClear(final INodeFile file,
       final BlocksMapUpdateInfo info, final List<INode> removedINodes) {
     // check if everything is deleted.
     if (isCurrentFileDeleted() && getDiffs().asList().isEmpty()) {
@@ -174,13 +176,19 @@ public class FileWithSnapshotFeature implements INode.Feature {
     }
     // find max file size.
     final long max;
+    FileDiff diff = getDiffs().getLast();
     if (isCurrentFileDeleted()) {
-      final FileDiff last = getDiffs().getLast();
+      max = diff == null? 0: diff.getFileSize();
-      max = last == null? 0: last.getFileSize();
     } else { 
       max = file.computeFileSize();
     }
 
-    file.collectBlocksBeyondMax(max, info);
+    // Collect blocks that should be deleted
+    FileDiff last = diffs.getLast();
+    BlockInfo[] snapshotBlocks = last == null ? null : last.getBlocks();
+    if(snapshotBlocks == null)
+      file.collectBlocksBeyondMax(max, info);
+    else
+      file.collectBlocksBeyondSnapshot(snapshotBlocks, info);
   }
 }

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

@@ -22,6 +22,7 @@ import java.util.ArrayList;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
+import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -53,8 +54,8 @@ public class BlockRecoveryCommand extends DatanodeCommand {
   @InterfaceAudience.Private
   @InterfaceStability.Evolving
   public static class RecoveringBlock extends LocatedBlock {
-    private boolean truncate;
     private final long newGenerationStamp;
+    private final Block recoveryBlock;
 
     /**
      * Create RecoveringBlock.
@@ -62,15 +63,17 @@ public class BlockRecoveryCommand extends DatanodeCommand {
     public RecoveringBlock(ExtendedBlock b, DatanodeInfo[] locs, long newGS) {
       super(b, locs, -1, false); // startOffset is unknown
       this.newGenerationStamp = newGS;
+      this.recoveryBlock = null;
     }
 
     /**
-     * RecoveryingBlock with truncate option.
+     * Create RecoveringBlock with copy-on-truncate option.
      */
-    public RecoveringBlock(ExtendedBlock b, DatanodeInfo[] locs, long newGS,
+    public RecoveringBlock(ExtendedBlock b, DatanodeInfo[] locs,
-                           boolean truncate) {
+        Block recoveryBlock) {
-      this(b, locs, newGS);
+      super(b, locs, -1, false); // startOffset is unknown
-      this.truncate = truncate;
+      this.newGenerationStamp = recoveryBlock.getGenerationStamp();
+      this.recoveryBlock = recoveryBlock;
     }
 
     /**
@@ -82,10 +85,10 @@ public class BlockRecoveryCommand extends DatanodeCommand {
     }
 
     /**
-     * Return whether to truncate the block to the ExtendedBlock's length.
+     * Return the new block.
      */
-    public boolean getTruncateFlag() {
+    public Block getNewBlock() {
-      return truncate;
+      return recoveryBlock;
     }
   }
 

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

@@ -67,5 +67,6 @@ public interface InterDatanodeProtocol {
    * Update replica with the new generation stamp and length.  
    */
   String updateReplicaUnderRecovery(ExtendedBlock oldBlock, long recoveryId,
-      long newLength) throws IOException;
+                                    long newBlockId, long newLength)
+      throws IOException;
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/proto/InterDatanodeProtocol.proto

@@ -59,6 +59,8 @@ message UpdateReplicaUnderRecoveryRequestProto {
   required ExtendedBlockProto block = 1; // Block identifier
   required uint64 recoveryId = 2;        // New genstamp of the replica
   required uint64 newLength = 3;         // New length of the replica
+  // New blockId for copy (truncate), default is 0.
+  optional uint64 newBlockId = 4 [default = 0];
 }
 
 /**

hadoop-hdfs-project/hadoop-hdfs/src/main/proto/fsimage.proto

@@ -270,6 +270,7 @@ message SnapshotDiffSection {
     optional uint64 fileSize = 2;
     optional bytes name = 3;
     optional INodeSection.INodeFile snapshotCopy = 4;
+    repeated BlockProto blocks = 5;
   }
 
   message DiffEntry {

hadoop-hdfs-project/hadoop-hdfs/src/main/proto/hdfs.proto

@@ -554,9 +554,9 @@ enum ReplicaStateProto {
  * Block that needs to be recovered with at a given location
  */
 message RecoveringBlockProto {
-  required uint64 newGenStamp = 1;      // New genstamp post recovery
+  required uint64 newGenStamp = 1;        // New genstamp post recovery
-  required LocatedBlockProto block = 2; // Block to be recovered
+  required LocatedBlockProto block = 2;   // Block to be recovered
-  optional bool truncateFlag = 3;       // Block needs to be truncated
+  optional BlockProto truncateBlock = 3;  // New block for recovery (truncate)
 }
 
 /**

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/SimulatedFSDataset.java

@@ -1113,6 +1113,7 @@ public class SimulatedFSDataset implements FsDatasetSpi<FsVolumeSpi> {
   @Override // FsDatasetSpi
   public String updateReplicaUnderRecovery(ExtendedBlock oldBlock,
                                         long recoveryId,
+                                        long newBlockId,
                                         long newlength) {
     // Caller does not care about the exact Storage UUID returned.
     return datanodeUuid;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestBlockRecovery.java

@@ -56,7 +56,6 @@ import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
-import org.apache.hadoop.hdfs.MiniDFSNNTopology;
 import org.apache.hadoop.hdfs.StorageType;
 import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
@@ -217,9 +216,9 @@ public class TestBlockRecovery {
     syncList.add(record2);
     
     when(dn1.updateReplicaUnderRecovery((ExtendedBlock)anyObject(), anyLong(),
-        anyLong())).thenReturn("storage1");
+        anyLong(), anyLong())).thenReturn("storage1");
     when(dn2.updateReplicaUnderRecovery((ExtendedBlock)anyObject(), anyLong(),
-        anyLong())).thenReturn("storage2");
+        anyLong(), anyLong())).thenReturn("storage2");
     dn.syncBlock(rBlock, syncList);
   }
   
@@ -242,8 +241,10 @@ public class TestBlockRecovery {
     InterDatanodeProtocol dn2 = mock(InterDatanodeProtocol.class);
 
     testSyncReplicas(replica1, replica2, dn1, dn2, REPLICA_LEN1);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
-    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);    
+        REPLICA_LEN1);
+    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
+        REPLICA_LEN1);
 
     // two finalized replicas have different length
     replica1 = new ReplicaRecoveryInfo(BLOCK_ID, 
@@ -281,8 +282,10 @@ public class TestBlockRecovery {
     InterDatanodeProtocol dn2 = mock(InterDatanodeProtocol.class);
 
     testSyncReplicas(replica1, replica2, dn1, dn2, REPLICA_LEN1);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
-    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+        REPLICA_LEN1);
+    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
+        REPLICA_LEN1);
     
     // rbw replica has a different length from the finalized one
     replica1 = new ReplicaRecoveryInfo(BLOCK_ID, 
@@ -294,9 +297,9 @@ public class TestBlockRecovery {
     dn2 = mock(InterDatanodeProtocol.class);
 
     testSyncReplicas(replica1, replica2, dn1, dn2, REPLICA_LEN1);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID, REPLICA_LEN1);
     verify(dn2, never()).updateReplicaUnderRecovery(
-        block, RECOVERY_ID, REPLICA_LEN1);
+        block, RECOVERY_ID, BLOCK_ID, REPLICA_LEN1);
   }
   
   /**
@@ -320,9 +323,10 @@ public class TestBlockRecovery {
     InterDatanodeProtocol dn2 = mock(InterDatanodeProtocol.class);
 
     testSyncReplicas(replica1, replica2, dn1, dn2, REPLICA_LEN1);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
+        REPLICA_LEN1);
     verify(dn2, never()).updateReplicaUnderRecovery(
-        block, RECOVERY_ID, REPLICA_LEN1);
+        block, RECOVERY_ID, BLOCK_ID, REPLICA_LEN1);
     
     // rbw replica has a different length from the finalized one
     replica1 = new ReplicaRecoveryInfo(BLOCK_ID, 
@@ -334,9 +338,10 @@ public class TestBlockRecovery {
     dn2 = mock(InterDatanodeProtocol.class);
 
     testSyncReplicas(replica1, replica2, dn1, dn2, REPLICA_LEN1);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
+        REPLICA_LEN1);
     verify(dn2, never()).updateReplicaUnderRecovery(
-        block, RECOVERY_ID, REPLICA_LEN1);
+        block, RECOVERY_ID, BLOCK_ID, REPLICA_LEN1);
   }
   
   /**
@@ -359,8 +364,8 @@ public class TestBlockRecovery {
 
     long minLen = Math.min(REPLICA_LEN1, REPLICA_LEN2);
     testSyncReplicas(replica1, replica2, dn1, dn2, minLen);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, minLen);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID, minLen);
-    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, minLen);    
+    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID, minLen);
   }
   
   /**
@@ -382,9 +387,10 @@ public class TestBlockRecovery {
     InterDatanodeProtocol dn2 = mock(InterDatanodeProtocol.class);
 
     testSyncReplicas(replica1, replica2, dn1, dn2, REPLICA_LEN1);
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, REPLICA_LEN1);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID,
+        REPLICA_LEN1);
     verify(dn2, never()).updateReplicaUnderRecovery(
-        block, RECOVERY_ID, REPLICA_LEN1);    
+        block, RECOVERY_ID, BLOCK_ID, REPLICA_LEN1);
   }
   
   /**
@@ -408,8 +414,8 @@ public class TestBlockRecovery {
     long minLen = Math.min(REPLICA_LEN1, REPLICA_LEN2);
     testSyncReplicas(replica1, replica2, dn1, dn2, minLen);
     
-    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, minLen);
+    verify(dn1).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID, minLen);
-    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, minLen);    
+    verify(dn2).updateReplicaUnderRecovery(block, RECOVERY_ID, BLOCK_ID, minLen);
   }  
 
   private Collection<RecoveringBlock> initRecoveringBlocks() throws IOException {
@@ -510,7 +516,7 @@ public class TestBlockRecovery {
     }
     DataNode spyDN = spy(dn);
     doThrow(new IOException()).when(spyDN).updateReplicaUnderRecovery(
-        block, RECOVERY_ID, block.getNumBytes());
+        block, RECOVERY_ID, BLOCK_ID, block.getNumBytes());
     try {
       spyDN.syncBlock(rBlock, initBlockRecords(spyDN));
       fail("Sync should fail");
@@ -631,7 +637,8 @@ public class TestBlockRecovery {
           recoveryInitResult.get());
       
       dataNode.updateReplicaUnderRecovery(block.getBlock(), block.getBlock()
-          .getGenerationStamp() + 1, block.getBlockSize());
+          .getGenerationStamp() + 1, block.getBlock().getBlockId(),
+          block.getBlockSize());
     } finally {
       if (null != cluster) {
         cluster.shutdown();

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestInterDatanodeProtocol.java

@@ -198,7 +198,8 @@ public class TestInterDatanodeProtocol {
       //verify updateBlock
       ExtendedBlock newblock = new ExtendedBlock(b.getBlockPoolId(),
           b.getBlockId(), b.getNumBytes()/2, b.getGenerationStamp()+1);
-      idp.updateReplicaUnderRecovery(b, recoveryId, newblock.getNumBytes());
+      idp.updateReplicaUnderRecovery(b, recoveryId, b.getBlockId(),
+          newblock.getNumBytes());
       checkMetaInfo(newblock, datanode);
       
       // Verify correct null response trying to init recovery for a missing block
@@ -368,7 +369,8 @@ public class TestInterDatanodeProtocol {
             .getBlockId(), rri.getNumBytes() - 1, rri.getGenerationStamp());
         try {
           //update should fail
-          fsdataset.updateReplicaUnderRecovery(tmp, recoveryid, newlength);
+          fsdataset.updateReplicaUnderRecovery(tmp, recoveryid,
+              tmp.getBlockId(), newlength);
           Assert.fail();
         } catch(IOException ioe) {
           System.out.println("GOOD: getting " + ioe);
@@ -377,7 +379,8 @@ public class TestInterDatanodeProtocol {
 
       //update
       final String storageID = fsdataset.updateReplicaUnderRecovery(
-          new ExtendedBlock(b.getBlockPoolId(), rri), recoveryid, newlength);
+          new ExtendedBlock(b.getBlockPoolId(), rri), recoveryid,
+          rri.getBlockId(), newlength);
       assertTrue(storageID != null);
 
     } finally {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestCommitBlockSynchronization.java

@@ -71,6 +71,7 @@ public class TestCommitBlockSynchronization {
     doReturn(true).when(file).isUnderConstruction();
 
     doReturn(blockInfo).when(namesystemSpy).getStoredBlock(any(Block.class));
+    doReturn(blockInfo).when(file).getLastBlock();
     doReturn("").when(namesystemSpy).closeFileCommitBlocks(
         any(INodeFile.class), any(BlockInfo.class));
     doReturn(mock(FSEditLog.class)).when(namesystemSpy).getEditLog();
@@ -105,6 +106,7 @@ public class TestCommitBlockSynchronization {
     completedBlockInfo.setGenerationStamp(genStamp);
     doReturn(completedBlockInfo).when(namesystemSpy)
         .getStoredBlock(any(Block.class));
+    doReturn(completedBlockInfo).when(file).getLastBlock();
 
     // Repeat the call to make sure it does not throw
     namesystemSpy.commitBlockSynchronization(
@@ -176,6 +178,7 @@ public class TestCommitBlockSynchronization {
     completedBlockInfo.setGenerationStamp(genStamp);
     doReturn(completedBlockInfo).when(namesystemSpy)
         .getStoredBlock(any(Block.class));
+    doReturn(completedBlockInfo).when(file).getLastBlock();
 
     namesystemSpy.commitBlockSynchronization(
         lastBlock, genStamp, length, true, false, newTargets, null);

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFileTruncate.java

@@ -18,14 +18,22 @@
 
 package org.apache.hadoop.hdfs.server.namenode;
 
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.not;
 import static org.hamcrest.core.Is.is;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
 import java.io.IOException;
-import java.net.InetAddress;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.ContentSummary;
 import org.apache.hadoop.fs.FSDataOutputStream;
@@ -39,14 +47,14 @@ import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
+import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
-import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfoUnderConstruction;
-import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor;
-import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeStorageInfo;
-import org.apache.hadoop.hdfs.server.common.GenerationStamp;
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
+import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.StartupOption;
+import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.test.GenericTestUtils;
+import org.apache.hadoop.util.Time;
 import org.apache.log4j.Level;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
@@ -57,6 +65,7 @@ public class TestFileTruncate {
     GenericTestUtils.setLogLevel(NameNode.stateChangeLog, Level.ALL);
     GenericTestUtils.setLogLevel(FSEditLogLoader.LOG, Level.ALL);
   }
+  static final Log LOG = LogFactory.getLog(TestFileTruncate.class);
   static final int BLOCK_SIZE = 4;
   static final short REPLICATION = 3;
   static final int DATANODE_NUM = 3;
@@ -129,6 +138,287 @@ public class TestFileTruncate {
     fs.delete(parent, true);
   }
 
+  @Test
+  public void testSnapshotWithAppendTruncate() throws IOException {
+    testSnapshotWithAppendTruncate(0, 1, 2);
+    testSnapshotWithAppendTruncate(0, 2, 1);
+    testSnapshotWithAppendTruncate(1, 0, 2);
+    testSnapshotWithAppendTruncate(1, 2, 0);
+    testSnapshotWithAppendTruncate(2, 0, 1);
+    testSnapshotWithAppendTruncate(2, 1, 0);
+  }
+
+  /**
+   * Create three snapshots with appended and truncated file.
+   * Delete snapshots in the specified order and verify that
+   * remaining snapshots are still readable.
+   */
+  void testSnapshotWithAppendTruncate(int ... deleteOrder) throws IOException {
+    FSDirectory fsDir = cluster.getNamesystem().getFSDirectory();
+    Path parent = new Path("/test");
+    fs.mkdirs(parent);
+    fs.setQuota(parent, 100, 1000);
+    fs.allowSnapshot(parent);
+    String truncateFile = "testSnapshotWithAppendTruncate";
+    final Path src = new Path(parent, truncateFile);
+    int[] length = new int[4];
+    length[0] = 2 * BLOCK_SIZE + BLOCK_SIZE / 2;
+    DFSTestUtil.createFile(fs, src, 64, length[0], BLOCK_SIZE, REPLICATION, 0L);
+    Block firstBlk = getLocatedBlocks(src).get(0).getBlock().getLocalBlock();
+    Path[] snapshotFiles = new Path[4];
+
+    // Diskspace consumed should be 10 bytes * 3. [blk 1,2,3]
+    ContentSummary contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(30L));
+
+    // Add file to snapshot and append
+    String[] ss = new String[] {"ss0", "ss1", "ss2", "ss3"};
+    Path snapshotDir = fs.createSnapshot(parent, ss[0]);
+    snapshotFiles[0] = new Path(snapshotDir, truncateFile);
+    length[1] = length[2] = length[0] + BLOCK_SIZE + 1;
+    DFSTestUtil.appendFile(fs, src, BLOCK_SIZE + 1);
+    Block lastBlk = getLocatedBlocks(src).getLastLocatedBlock()
+                                         .getBlock().getLocalBlock();
+
+    // Diskspace consumed should be 15 bytes * 3. [blk 1,2,3,4]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(45L));
+
+    // Create another snapshot without changes
+    snapshotDir = fs.createSnapshot(parent, ss[1]);
+    snapshotFiles[1] = new Path(snapshotDir, truncateFile);
+
+    // Create another snapshot and append
+    snapshotDir = fs.createSnapshot(parent, ss[2]);
+    snapshotFiles[2] = new Path(snapshotDir, truncateFile);
+    DFSTestUtil.appendFile(fs, src, BLOCK_SIZE -1 + BLOCK_SIZE / 2);
+    Block appendedBlk = getLocatedBlocks(src).getLastLocatedBlock()
+                                             .getBlock().getLocalBlock();
+
+    // Diskspace consumed should be 20 bytes * 3. [blk 1,2,3,4,5]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(60L));
+
+    // Truncate to block boundary
+    int newLength = length[0] + BLOCK_SIZE / 2;
+    boolean isReady = fs.truncate(src, newLength);
+    assertTrue("Recovery is not expected.", isReady);
+    assertFileLength(snapshotFiles[2], length[2]);
+    assertFileLength(snapshotFiles[1], length[1]);
+    assertFileLength(snapshotFiles[0], length[0]);
+    assertBlockNotPresent(appendedBlk);
+
+    // Diskspace consumed should be 16 bytes * 3. [blk 1,2,3 SS:4]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(48L));
+
+    // Truncate full block again
+    newLength = length[0] - BLOCK_SIZE / 2;
+    isReady = fs.truncate(src, newLength);
+    assertTrue("Recovery is not expected.", isReady);
+    assertFileLength(snapshotFiles[2], length[2]);
+    assertFileLength(snapshotFiles[1], length[1]);
+    assertFileLength(snapshotFiles[0], length[0]);
+
+    // Diskspace consumed should be 16 bytes * 3. [blk 1,2 SS:3,4]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(48L));
+
+    // Truncate half of the last block
+    newLength -= BLOCK_SIZE / 2;
+    isReady = fs.truncate(src, newLength);
+    assertFalse("Recovery is expected.", isReady);
+    checkBlockRecovery(src);
+    assertFileLength(snapshotFiles[2], length[2]);
+    assertFileLength(snapshotFiles[1], length[1]);
+    assertFileLength(snapshotFiles[0], length[0]);
+    Block replacedBlk = getLocatedBlocks(src).getLastLocatedBlock()
+        .getBlock().getLocalBlock();
+
+    // Diskspace consumed should be 16 bytes * 3. [blk 1,6 SS:2,3,4]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(54L));
+
+    snapshotDir = fs.createSnapshot(parent, ss[3]);
+    snapshotFiles[3] = new Path(snapshotDir, truncateFile);
+    length[3] = newLength;
+
+    // Delete file. Should still be able to read snapshots
+    int numINodes = fsDir.getInodeMapSize();
+    isReady = fs.delete(src, false);
+    assertTrue("Delete failed.", isReady);
+    assertFileLength(snapshotFiles[3], length[3]);
+    assertFileLength(snapshotFiles[2], length[2]);
+    assertFileLength(snapshotFiles[1], length[1]);
+    assertFileLength(snapshotFiles[0], length[0]);
+    assertEquals("Number of INodes should not change",
+        numINodes, fsDir.getInodeMapSize());
+
+    fs.deleteSnapshot(parent, ss[3]);
+
+    assertBlockExists(firstBlk);
+    assertBlockExists(lastBlk);
+    assertBlockNotPresent(replacedBlk);
+
+    // Diskspace consumed should be 16 bytes * 3. [SS:1,2,3,4]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(48L));
+
+    // delete snapshots in the specified order
+    fs.deleteSnapshot(parent, ss[deleteOrder[0]]);
+    assertFileLength(snapshotFiles[deleteOrder[1]], length[deleteOrder[1]]);
+    assertFileLength(snapshotFiles[deleteOrder[2]], length[deleteOrder[2]]);
+    assertBlockExists(firstBlk);
+    assertBlockExists(lastBlk);
+    assertEquals("Number of INodes should not change",
+        numINodes, fsDir.getInodeMapSize());
+
+    // Diskspace consumed should be 16 bytes * 3. [SS:1,2,3,4]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(48L));
+
+    fs.deleteSnapshot(parent, ss[deleteOrder[1]]);
+    assertFileLength(snapshotFiles[deleteOrder[2]], length[deleteOrder[2]]);
+    assertBlockExists(firstBlk);
+    contentSummary = fs.getContentSummary(parent);
+    if(fs.exists(snapshotFiles[0])) {
+      // Diskspace consumed should be 0 bytes * 3. [SS:1,2,3]
+      assertBlockNotPresent(lastBlk);
+      assertThat(contentSummary.getSpaceConsumed(), is(36L));
+    } else {
+      // Diskspace consumed should be 48 bytes * 3. [SS:1,2,3,4]
+      assertThat(contentSummary.getSpaceConsumed(), is(48L));
+    }
+    assertEquals("Number of INodes should not change",
+        numINodes, fsDir .getInodeMapSize());
+
+    fs.deleteSnapshot(parent, ss[deleteOrder[2]]);
+    assertBlockNotPresent(firstBlk);
+    assertBlockNotPresent(lastBlk);
+
+    // Diskspace consumed should be 0 bytes * 3. []
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(0L));
+    assertNotEquals("Number of INodes should change",
+        numINodes, fsDir.getInodeMapSize());
+  }
+
+  /**
+   * Create three snapshots with file truncated 3 times.
+   * Delete snapshots in the specified order and verify that
+   * remaining snapshots are still readable.
+   */
+  @Test
+  public void testSnapshotWithTruncates() throws IOException {
+    testSnapshotWithTruncates(0, 1, 2);
+    testSnapshotWithTruncates(0, 2, 1);
+    testSnapshotWithTruncates(1, 0, 2);
+    testSnapshotWithTruncates(1, 2, 0);
+    testSnapshotWithTruncates(2, 0, 1);
+    testSnapshotWithTruncates(2, 1, 0);
+  }
+
+  void testSnapshotWithTruncates(int ... deleteOrder) throws IOException {
+    Path parent = new Path("/test");
+    fs.mkdirs(parent);
+    fs.setQuota(parent, 100, 1000);
+    fs.allowSnapshot(parent);
+    String truncateFile = "testSnapshotWithTruncates";
+    final Path src = new Path(parent, truncateFile);
+    int[] length = new int[3];
+    length[0] = 3 * BLOCK_SIZE;
+    DFSTestUtil.createFile(fs, src, 64, length[0], BLOCK_SIZE, REPLICATION, 0L);
+    Block firstBlk = getLocatedBlocks(src).get(0).getBlock().getLocalBlock();
+    Block lastBlk = getLocatedBlocks(src).getLastLocatedBlock()
+                                         .getBlock().getLocalBlock();
+    Path[] snapshotFiles = new Path[3];
+
+    // Diskspace consumed should be 12 bytes * 3. [blk 1,2,3]
+    ContentSummary contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(36L));
+
+    // Add file to snapshot and append
+    String[] ss = new String[] {"ss0", "ss1", "ss2"};
+    Path snapshotDir = fs.createSnapshot(parent, ss[0]);
+    snapshotFiles[0] = new Path(snapshotDir, truncateFile);
+    length[1] = 2 * BLOCK_SIZE;
+    boolean isReady = fs.truncate(src, 2 * BLOCK_SIZE);
+    assertTrue("Recovery is not expected.", isReady);
+
+    // Diskspace consumed should be 12 bytes * 3. [blk 1,2 SS:3]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(36L));
+    snapshotDir = fs.createSnapshot(parent, ss[1]);
+    snapshotFiles[1] = new Path(snapshotDir, truncateFile);
+
+    // Create another snapshot with truncate
+    length[2] = BLOCK_SIZE + BLOCK_SIZE / 2;
+    isReady = fs.truncate(src, BLOCK_SIZE + BLOCK_SIZE / 2);
+    assertFalse("Recovery is expected.", isReady);
+    checkBlockRecovery(src);
+    snapshotDir = fs.createSnapshot(parent, ss[2]);
+    snapshotFiles[2] = new Path(snapshotDir, truncateFile);
+    assertFileLength(snapshotFiles[0], length[0]);
+    assertBlockExists(lastBlk);
+
+    // Diskspace consumed should be 14 bytes * 3. [blk 1,4 SS:2,3]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(42L));
+
+    fs.deleteSnapshot(parent, ss[deleteOrder[0]]);
+    assertFileLength(snapshotFiles[deleteOrder[1]], length[deleteOrder[1]]);
+    assertFileLength(snapshotFiles[deleteOrder[2]], length[deleteOrder[2]]);
+    assertFileLength(src, length[2]);
+    assertBlockExists(firstBlk);
+
+    contentSummary = fs.getContentSummary(parent);
+    if(fs.exists(snapshotFiles[0])) {
+      // Diskspace consumed should be 14 bytes * 3. [blk 1,4 SS:2,3]
+      assertThat(contentSummary.getSpaceConsumed(), is(42L));
+      assertBlockExists(lastBlk);
+    } else {
+      // Diskspace consumed should be 10 bytes * 3. [blk 1,4 SS:2]
+      assertThat(contentSummary.getSpaceConsumed(), is(30L));
+      assertBlockNotPresent(lastBlk);
+    }
+
+    fs.deleteSnapshot(parent, ss[deleteOrder[1]]);
+    assertFileLength(snapshotFiles[deleteOrder[2]], length[deleteOrder[2]]);
+    assertFileLength(src, length[2]);
+    assertBlockExists(firstBlk);
+
+    contentSummary = fs.getContentSummary(parent);
+    if(fs.exists(snapshotFiles[0])) {
+      // Diskspace consumed should be 14 bytes * 3. [blk 1,4 SS:2,3]
+      assertThat(contentSummary.getSpaceConsumed(), is(42L));
+      assertBlockExists(lastBlk);
+    } else if(fs.exists(snapshotFiles[1])) {
+      // Diskspace consumed should be 10 bytes * 3. [blk 1,4 SS:2]
+      assertThat(contentSummary.getSpaceConsumed(), is(30L));
+      assertBlockNotPresent(lastBlk);
+    } else {
+      // Diskspace consumed should be 6 bytes * 3. [blk 1,4 SS:]
+      assertThat(contentSummary.getSpaceConsumed(), is(18L));
+      assertBlockNotPresent(lastBlk);
+    }
+
+    fs.deleteSnapshot(parent, ss[deleteOrder[2]]);
+    assertFileLength(src, length[2]);
+    assertBlockExists(firstBlk);
+
+    // Diskspace consumed should be 6 bytes * 3. [blk 1,4 SS:]
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(18L));
+    assertThat(contentSummary.getLength(), is(6L));
+
+    fs.delete(src, false);
+    assertBlockNotPresent(firstBlk);
+
+    // Diskspace consumed should be 0 bytes * 3. []
+    contentSummary = fs.getContentSummary(parent);
+    assertThat(contentSummary.getSpaceConsumed(), is(0L));
+  }
+
   /**
    * Failure / recovery test for truncate.
    * In this failure the DNs fail to recover the blocks and the NN triggers
@@ -159,8 +449,6 @@ public class TestFileTruncate {
     boolean isReady = fs.truncate(p, newLength);
     assertThat("truncate should have triggered block recovery.",
         isReady, is(false));
-    FileStatus fileStatus = fs.getFileStatus(p);
-    assertThat(fileStatus.getLen(), is((long) newLength));
 
     boolean recoveryTriggered = false;
     for(int i = 0; i < RECOVERY_ATTEMPTS; i++) {
@@ -168,8 +456,6 @@ public class TestFileTruncate {
           NameNodeAdapter.getLeaseHolderForPath(cluster.getNameNode(),
           p.toUri().getPath());
       if(leaseHolder.equals(HdfsServerConstants.NAMENODE_LEASE_HOLDER)) {
-        cluster.startDataNodes(conf, DATANODE_NUM, true,
-            HdfsServerConstants.StartupOption.REGULAR, null);
         recoveryTriggered = true;
         break;
       }
@@ -177,6 +463,9 @@ public class TestFileTruncate {
     }
     assertThat("lease recovery should have occurred in ~" +
         SLEEP * RECOVERY_ATTEMPTS + " ms.", recoveryTriggered, is(true));
+    cluster.startDataNodes(conf, DATANODE_NUM, true,
+        StartupOption.REGULAR, null);
+    cluster.waitActive();
 
     checkBlockRecovery(p);
 
@@ -184,10 +473,10 @@ public class TestFileTruncate {
         .setLeasePeriod(HdfsConstants.LEASE_SOFTLIMIT_PERIOD,
             HdfsConstants.LEASE_HARDLIMIT_PERIOD);
 
-    fileStatus = fs.getFileStatus(p);
+    FileStatus fileStatus = fs.getFileStatus(p);
     assertThat(fileStatus.getLen(), is((long) newLength));
 
-    AppendTestUtil.checkFullFile(fs, p, newLength, contents, p.toString());
+    checkFullFile(p, newLength, contents);
     fs.delete(p, false);
   }
 
@@ -198,10 +487,9 @@ public class TestFileTruncate {
   public void testTruncateEditLogLoad() throws IOException {
     int startingFileSize = 2 * BLOCK_SIZE + BLOCK_SIZE / 2;
     int toTruncate = 1;
-
+    final String s = "/testTruncateEditLogLoad";
+    final Path p = new Path(s);
     byte[] contents = AppendTestUtil.initBuffer(startingFileSize);
-
-    final Path p = new Path("/testTruncateEditLogLoad");
     writeContents(contents, startingFileSize, p);
 
     int newLength = startingFileSize - toTruncate;
@@ -209,54 +497,183 @@ public class TestFileTruncate {
     assertThat("truncate should have triggered block recovery.",
         isReady, is(false));
 
-    checkBlockRecovery(p);
-
     cluster.restartNameNode();
 
+    String holder = UserGroupInformation.getCurrentUser().getUserName();
+    cluster.getNamesystem().recoverLease(s, holder, "");
+
+    checkBlockRecovery(p);
+
     FileStatus fileStatus = fs.getFileStatus(p);
     assertThat(fileStatus.getLen(), is((long) newLength));
 
-    AppendTestUtil.checkFullFile(fs, p, newLength, contents, p.toString());
+    checkFullFile(p, newLength, contents);
     fs.delete(p, false);
   }
 
+  /**
+   * Upgrade, RollBack, and restart test for Truncate.
+   */
+  @Test
+  public void testUpgradeAndRestart() throws IOException {
+    Path parent = new Path("/test");
+    fs.mkdirs(parent);
+    fs.setQuota(parent, 100, 1000);
+    fs.allowSnapshot(parent);
+    String truncateFile = "testUpgrade";
+    final Path p = new Path(parent, truncateFile);
+    int startingFileSize = 2 * BLOCK_SIZE;
+    int toTruncate = 1;
+    byte[] contents = AppendTestUtil.initBuffer(startingFileSize);
+    writeContents(contents, startingFileSize, p);
+
+    Path snapshotDir = fs.createSnapshot(parent, "ss0");
+    Path snapshotFile = new Path(snapshotDir, truncateFile);
+
+    int newLengthBeforeUpgrade = startingFileSize - toTruncate;
+    boolean isReady = fs.truncate(p, newLengthBeforeUpgrade);
+    assertThat("truncate should have triggered block recovery.",
+        isReady, is(false));
+
+    checkBlockRecovery(p);
+
+    checkFullFile(p, newLengthBeforeUpgrade, contents);
+    assertFileLength(snapshotFile, startingFileSize);
+    long totalBlockBefore = cluster.getNamesystem().getBlocksTotal();
+
+    restartCluster(StartupOption.UPGRADE);
+
+    assertThat("SafeMode should be OFF",
+        cluster.getNamesystem().isInSafeMode(), is(false));
+    assertThat("NameNode should be performing upgrade.",
+        cluster.getNamesystem().isUpgradeFinalized(), is(false));
+    FileStatus fileStatus = fs.getFileStatus(p);
+    assertThat(fileStatus.getLen(), is((long) newLengthBeforeUpgrade));
+
+    int newLengthAfterUpgrade = newLengthBeforeUpgrade - toTruncate;
+    Block oldBlk = getLocatedBlocks(p).getLastLocatedBlock()
+        .getBlock().getLocalBlock();
+    isReady = fs.truncate(p, newLengthAfterUpgrade);
+    assertThat("truncate should have triggered block recovery.",
+        isReady, is(false));
+    fileStatus = fs.getFileStatus(p);
+    assertThat(fileStatus.getLen(), is((long) newLengthAfterUpgrade));
+    assertThat("Should copy on truncate during upgrade",
+        getLocatedBlocks(p).getLastLocatedBlock().getBlock()
+        .getLocalBlock().getBlockId(), is(not(equalTo(oldBlk.getBlockId()))));
+
+    checkBlockRecovery(p);
+
+    checkFullFile(p, newLengthAfterUpgrade, contents);
+    assertThat("Total block count should be unchanged from copy-on-truncate",
+        cluster.getNamesystem().getBlocksTotal(), is(totalBlockBefore));
+
+    restartCluster(StartupOption.ROLLBACK);
+
+    assertThat("File does not exist " + p, fs.exists(p), is(true));
+    fileStatus = fs.getFileStatus(p);
+    assertThat(fileStatus.getLen(), is((long) newLengthBeforeUpgrade));
+    checkFullFile(p, newLengthBeforeUpgrade, contents);
+    assertThat("Total block count should be unchanged from rolling back",
+        cluster.getNamesystem().getBlocksTotal(), is(totalBlockBefore));
+
+    restartCluster(StartupOption.REGULAR);
+    assertThat("Total block count should be unchanged from start-up",
+        cluster.getNamesystem().getBlocksTotal(), is(totalBlockBefore));
+    checkFullFile(p, newLengthBeforeUpgrade, contents);
+    assertFileLength(snapshotFile, startingFileSize);
+
+    // empty edits and restart
+    fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
+    fs.saveNamespace();
+    cluster.restartNameNode(true);
+    assertThat("Total block count should be unchanged from start-up",
+        cluster.getNamesystem().getBlocksTotal(), is(totalBlockBefore));
+    checkFullFile(p, newLengthBeforeUpgrade, contents);
+    assertFileLength(snapshotFile, startingFileSize);
+
+    fs.deleteSnapshot(parent, "ss0");
+    fs.delete(parent, true);
+    assertThat("File " + p + " shouldn't exist", fs.exists(p), is(false));
+  }
+
   /**
    * Check truncate recovery.
    */
   @Test
-  public void testTruncateLastBlock() throws IOException {
+  public void testTruncateRecovery() throws IOException {
     FSNamesystem fsn = cluster.getNamesystem();
-
+    String client = "client";
-    String src = "/file";
+    String clientMachine = "clientMachine";
+    Path parent = new Path("/test");
+    String src = "/test/testTruncateRecovery";
     Path srcPath = new Path(src);
 
     byte[] contents = AppendTestUtil.initBuffer(BLOCK_SIZE);
     writeContents(contents, BLOCK_SIZE, srcPath);
 
-    INodeFile inode = fsn.getFSDirectory().getINode(src).asFile();
+    INodesInPath iip = fsn.getFSDirectory().getINodesInPath4Write(src, true);
-    long oldGenstamp = GenerationStamp.LAST_RESERVED_STAMP;
+    INodeFile file = iip.getLastINode().asFile();
-    DatanodeDescriptor dn = DFSTestUtil.getLocalDatanodeDescriptor();
+    long initialGenStamp = file.getLastBlock().getGenerationStamp();
-    DatanodeStorageInfo storage = DFSTestUtil.createDatanodeStorageInfo(
+    // Test that prepareFileForTruncate sets up in-place truncate.
-        dn.getDatanodeUuid(), InetAddress.getLocalHost().getHostAddress());
-    dn.isAlive = true;
-
-    BlockInfoUnderConstruction blockInfo = new BlockInfoUnderConstruction(
-        new Block(0, 1, oldGenstamp), (short) 1,
-        HdfsServerConstants.BlockUCState.BEING_TRUNCATED,
-        new DatanodeStorageInfo[] {storage});
-
-    inode.setBlocks(new BlockInfo[] {blockInfo});
     fsn.writeLock();
     try {
-      fsn.initializeBlockRecovery(inode);
+      Block oldBlock = file.getLastBlock();
-      assertThat(inode.getLastBlock().getBlockUCState(),
+      Block truncateBlock =
-          is(HdfsServerConstants.BlockUCState.BEING_TRUNCATED));
+          fsn.prepareFileForTruncate(iip, client, clientMachine, 1, null);
-      long blockRecoveryId = ((BlockInfoUnderConstruction) inode.getLastBlock())
+      // In-place truncate uses old block id with new genStamp.
+      assertThat(truncateBlock.getBlockId(),
+          is(equalTo(oldBlock.getBlockId())));
+      assertThat(truncateBlock.getNumBytes(),
+          is(oldBlock.getNumBytes()));
+      assertThat(truncateBlock.getGenerationStamp(),
+          is(fsn.getBlockIdManager().getGenerationStampV2()));
+      assertThat(file.getLastBlock().getBlockUCState(),
+          is(HdfsServerConstants.BlockUCState.UNDER_RECOVERY));
+      long blockRecoveryId = ((BlockInfoUnderConstruction) file.getLastBlock())
           .getBlockRecoveryId();
-      assertThat(blockRecoveryId, is(oldGenstamp + 2));
+      assertThat(blockRecoveryId, is(initialGenStamp + 1));
+      fsn.getEditLog().logTruncate(
+          src, client, clientMachine, BLOCK_SIZE-1, Time.now(), truncateBlock);
     } finally {
       fsn.writeUnlock();
     }
+
+    // Re-create file and ensure we are ready to copy on truncate
+    writeContents(contents, BLOCK_SIZE, srcPath);
+    fs.allowSnapshot(parent);
+    fs.createSnapshot(parent, "ss0");
+    iip = fsn.getFSDirectory().getINodesInPath(src, true);
+    file = iip.getLastINode().asFile();
+    file.recordModification(iip.getLatestSnapshotId(), true);
+    assertThat(file.isBlockInLatestSnapshot(file.getLastBlock()), is(true));
+    initialGenStamp = file.getLastBlock().getGenerationStamp();
+    // Test that prepareFileForTruncate sets up copy-on-write truncate
+    fsn.writeLock();
+    try {
+      Block oldBlock = file.getLastBlock();
+      Block truncateBlock =
+          fsn.prepareFileForTruncate(iip, client, clientMachine, 1, null);
+      // Copy-on-write truncate makes new block with new id and genStamp
+      assertThat(truncateBlock.getBlockId(),
+          is(not(equalTo(oldBlock.getBlockId()))));
+      assertThat(truncateBlock.getNumBytes() < oldBlock.getNumBytes(),
+          is(true));
+      assertThat(truncateBlock.getGenerationStamp(),
+          is(fsn.getBlockIdManager().getGenerationStampV2()));
+      assertThat(file.getLastBlock().getBlockUCState(),
+          is(HdfsServerConstants.BlockUCState.UNDER_RECOVERY));
+      long blockRecoveryId = ((BlockInfoUnderConstruction) file.getLastBlock())
+          .getBlockRecoveryId();
+      assertThat(blockRecoveryId, is(initialGenStamp + 1));
+      fsn.getEditLog().logTruncate(
+          src, client, clientMachine, BLOCK_SIZE-1, Time.now(), truncateBlock);
+    } finally {
+      fsn.writeUnlock();
+    }
+    checkBlockRecovery(srcPath);
+    fs.deleteSnapshot(parent, "ss0");
+    fs.delete(parent, true);
   }
 
   static void writeContents(byte[] contents, int fileLength, Path p)
@@ -286,4 +703,38 @@ public class TestFileTruncate {
   static LocatedBlocks getLocatedBlocks(Path src) throws IOException {
     return fs.getClient().getLocatedBlocks(src.toString(), 0, Long.MAX_VALUE);
   }
+
+  static void assertBlockExists(Block blk) {
+    assertNotNull("BlocksMap does not contain block: " + blk,
+        cluster.getNamesystem().getStoredBlock(blk));
+  }
+
+  static void assertBlockNotPresent(Block blk) {
+    assertNull("BlocksMap should not contain block: " + blk,
+        cluster.getNamesystem().getStoredBlock(blk));
+  }
+
+  static void assertFileLength(Path file, long length) throws IOException {
+    byte[] data = DFSTestUtil.readFileBuffer(fs, file);
+    assertEquals("Wrong data size in snapshot.", length, data.length);
+  }
+
+  static void checkFullFile(Path p, int newLength, byte[] contents)
+      throws IOException {
+    AppendTestUtil.checkFullFile(fs, p, newLength, contents, p.toString());
+  }
+
+  static void restartCluster(StartupOption o)
+      throws IOException {
+    cluster.shutdown();
+    if(StartupOption.ROLLBACK == o)
+      NameNode.doRollback(conf, false);
+    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(DATANODE_NUM)
+        .format(false)
+        .nameNodePort(NameNode.DEFAULT_PORT)
+        .startupOption(o==StartupOption.ROLLBACK ? StartupOption.REGULAR : o)
+        .dnStartupOption(o!=StartupOption.ROLLBACK ? StartupOption.REGULAR : o)
+        .build();
+    fs = cluster.getFileSystem();
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/resources/editsStored.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <EDITS>
-  <EDITS_VERSION>-60</EDITS_VERSION>
+  <EDITS_VERSION>-61</EDITS_VERSION>
   <RECORD>
     <OPCODE>OP_START_LOG_SEGMENT</OPCODE>
     <DATA>
@@ -13,8 +13,8 @@
       <TXID>2</TXID>
       <DELEGATION_KEY>
         <KEY_ID>1</KEY_ID>
-        <EXPIRY_DATE>1421822547136</EXPIRY_DATE>
+        <EXPIRY_DATE>1421826999207</EXPIRY_DATE>
-        <KEY>24319c7d1f7c0828</KEY>
+        <KEY>ca9a0c8b240570b3</KEY>
       </DELEGATION_KEY>
     </DATA>
   </RECORD>
@@ -24,8 +24,8 @@
       <TXID>3</TXID>
       <DELEGATION_KEY>
         <KEY_ID>2</KEY_ID>
-        <EXPIRY_DATE>1421822547140</EXPIRY_DATE>
+        <EXPIRY_DATE>1421826999210</EXPIRY_DATE>
-        <KEY>254b1207021431f4</KEY>
+        <KEY>833c25a6fb2b0a6f</KEY>
       </DELEGATION_KEY>
     </DATA>
   </RECORD>
@@ -37,19 +37,19 @@
       <INODEID>16386</INODEID>
       <PATH>/file_create</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131348286</MTIME>
+      <MTIME>1421135800328</MTIME>
-      <ATIME>1421131348286</ATIME>
+      <ATIME>1421135800328</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>6</RPC_CALLID>
+      <RPC_CALLID>9</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -60,14 +60,14 @@
       <INODEID>0</INODEID>
       <PATH>/file_create</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131348328</MTIME>
+      <MTIME>1421135800357</MTIME>
-      <ATIME>1421131348286</ATIME>
+      <ATIME>1421135800328</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
       <OVERWRITE>false</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -88,9 +88,9 @@
       <LENGTH>0</LENGTH>
       <SRC>/file_create</SRC>
       <DST>/file_moved</DST>
-      <TIMESTAMP>1421131348343</TIMESTAMP>
+      <TIMESTAMP>1421135800368</TIMESTAMP>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>9</RPC_CALLID>
+      <RPC_CALLID>12</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -99,9 +99,9 @@
       <TXID>8</TXID>
       <LENGTH>0</LENGTH>
       <PATH>/file_moved</PATH>
-      <TIMESTAMP>1421131348353</TIMESTAMP>
+      <TIMESTAMP>1421135800377</TIMESTAMP>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>10</RPC_CALLID>
+      <RPC_CALLID>13</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -111,9 +111,9 @@
       <LENGTH>0</LENGTH>
       <INODEID>16387</INODEID>
       <PATH>/directory_mkdir</PATH>
-      <TIMESTAMP>1421131348366</TIMESTAMP>
+      <TIMESTAMP>1421135800394</TIMESTAMP>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>493</MODE>
       </PERMISSION_STATUS>
@@ -146,8 +146,8 @@
       <TXID>13</TXID>
       <SNAPSHOTROOT>/directory_mkdir</SNAPSHOTROOT>
       <SNAPSHOTNAME>snapshot1</SNAPSHOTNAME>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>15</RPC_CALLID>
+      <RPC_CALLID>18</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -157,8 +157,8 @@
       <SNAPSHOTROOT>/directory_mkdir</SNAPSHOTROOT>
       <SNAPSHOTOLDNAME>snapshot1</SNAPSHOTOLDNAME>
       <SNAPSHOTNEWNAME>snapshot2</SNAPSHOTNEWNAME>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>16</RPC_CALLID>
+      <RPC_CALLID>19</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -167,8 +167,8 @@
       <TXID>15</TXID>
       <SNAPSHOTROOT>/directory_mkdir</SNAPSHOTROOT>
       <SNAPSHOTNAME>snapshot2</SNAPSHOTNAME>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>17</RPC_CALLID>
+      <RPC_CALLID>20</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -179,19 +179,19 @@
       <INODEID>16388</INODEID>
       <PATH>/file_create</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131348401</MTIME>
+      <MTIME>1421135800442</MTIME>
-      <ATIME>1421131348401</ATIME>
+      <ATIME>1421135800442</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>18</RPC_CALLID>
+      <RPC_CALLID>21</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -202,14 +202,14 @@
       <INODEID>0</INODEID>
       <PATH>/file_create</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131348405</MTIME>
+      <MTIME>1421135800445</MTIME>
-      <ATIME>1421131348401</ATIME>
+      <ATIME>1421135800442</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
       <OVERWRITE>false</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -265,10 +265,10 @@
       <LENGTH>0</LENGTH>
       <SRC>/file_create</SRC>
       <DST>/file_moved</DST>
-      <TIMESTAMP>1421131348436</TIMESTAMP>
+      <TIMESTAMP>1421135800485</TIMESTAMP>
       <OPTIONS>NONE</OPTIONS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>25</RPC_CALLID>
+      <RPC_CALLID>28</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -279,19 +279,19 @@
       <INODEID>16389</INODEID>
       <PATH>/file_concat_target</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131348443</MTIME>
+      <MTIME>1421135800495</MTIME>
-      <ATIME>1421131348443</ATIME>
+      <ATIME>1421135800495</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>27</RPC_CALLID>
+      <RPC_CALLID>30</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -396,8 +396,8 @@
       <INODEID>0</INODEID>
       <PATH>/file_concat_target</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131348998</MTIME>
+      <MTIME>1421135801050</MTIME>
-      <ATIME>1421131348443</ATIME>
+      <ATIME>1421135800495</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
@@ -418,7 +418,7 @@
         <GENSTAMP>1003</GENSTAMP>
       </BLOCK>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -432,19 +432,19 @@
       <INODEID>16390</INODEID>
       <PATH>/file_concat_0</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349001</MTIME>
+      <MTIME>1421135801053</MTIME>
-      <ATIME>1421131349001</ATIME>
+      <ATIME>1421135801053</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>38</RPC_CALLID>
+      <RPC_CALLID>41</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -549,8 +549,8 @@
       <INODEID>0</INODEID>
       <PATH>/file_concat_0</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349032</MTIME>
+      <MTIME>1421135801091</MTIME>
-      <ATIME>1421131349001</ATIME>
+      <ATIME>1421135801053</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
@@ -571,7 +571,7 @@
         <GENSTAMP>1006</GENSTAMP>
       </BLOCK>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -585,19 +585,19 @@
       <INODEID>16391</INODEID>
       <PATH>/file_concat_1</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349036</MTIME>
+      <MTIME>1421135801095</MTIME>
-      <ATIME>1421131349036</ATIME>
+      <ATIME>1421135801095</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>47</RPC_CALLID>
+      <RPC_CALLID>50</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -702,8 +702,8 @@
       <INODEID>0</INODEID>
       <PATH>/file_concat_1</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349060</MTIME>
+      <MTIME>1421135801126</MTIME>
-      <ATIME>1421131349036</ATIME>
+      <ATIME>1421135801095</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
@@ -724,7 +724,7 @@
         <GENSTAMP>1009</GENSTAMP>
       </BLOCK>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -736,13 +736,13 @@
       <TXID>57</TXID>
       <LENGTH>0</LENGTH>
       <TRG>/file_concat_target</TRG>
-      <TIMESTAMP>1421131349064</TIMESTAMP>
+      <TIMESTAMP>1421135801130</TIMESTAMP>
       <SOURCES>
         <SOURCE1>/file_concat_0</SOURCE1>
         <SOURCE2>/file_concat_1</SOURCE2>
       </SOURCES>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>55</RPC_CALLID>
+      <RPC_CALLID>58</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -753,19 +753,19 @@
       <INODEID>16392</INODEID>
       <PATH>/file_create</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349068</MTIME>
+      <MTIME>1421135810102</MTIME>
-      <ATIME>1421131349068</ATIME>
+      <ATIME>1421135810102</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>57</RPC_CALLID>
+      <RPC_CALLID>63</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -837,8 +837,8 @@
       <INODEID>0</INODEID>
       <PATH>/file_create</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349085</MTIME>
+      <MTIME>1421135810122</MTIME>
-      <ATIME>1421131349068</ATIME>
+      <ATIME>1421135810102</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
@@ -854,7 +854,7 @@
         <GENSTAMP>1011</GENSTAMP>
       </BLOCK>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -865,10 +865,10 @@
     <DATA>
       <TXID>66</TXID>
       <SRC>/file_create</SRC>
-      <CLIENTNAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENTNAME>
+      <CLIENTNAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENTNAME>
       <CLIENTMACHINE>127.0.0.1</CLIENTMACHINE>
       <NEWLENGTH>512</NEWLENGTH>
-      <TIMESTAMP>1421131349088</TIMESTAMP>
+      <TIMESTAMP>1421135810125</TIMESTAMP>
     </DATA>
   </RECORD>
   <RECORD>
@@ -879,15 +879,15 @@
       <INODEID>16393</INODEID>
       <PATH>/file_symlink</PATH>
       <VALUE>/file_concat_target</VALUE>
-      <MTIME>1421131349095</MTIME>
+      <MTIME>1421135810132</MTIME>
-      <ATIME>1421131349095</ATIME>
+      <ATIME>1421135810132</ATIME>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>511</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>64</RPC_CALLID>
+      <RPC_CALLID>70</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -898,19 +898,19 @@
       <INODEID>16394</INODEID>
       <PATH>/hard-lease-recovery-test</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131349098</MTIME>
+      <MTIME>1421135810135</MTIME>
-      <ATIME>1421131349098</ATIME>
+      <ATIME>1421135810135</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
-      <CLIENT_NAME>DFSClient_NONMAPREDUCE_526346936_1</CLIENT_NAME>
+      <CLIENT_NAME>DFSClient_NONMAPREDUCE_240777107_1</CLIENT_NAME>
       <CLIENT_MACHINE>127.0.0.1</CLIENT_MACHINE>
       <OVERWRITE>true</OVERWRITE>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>65</RPC_CALLID>
+      <RPC_CALLID>71</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -966,7 +966,7 @@
     <OPCODE>OP_REASSIGN_LEASE</OPCODE>
     <DATA>
       <TXID>74</TXID>
-      <LEASEHOLDER>DFSClient_NONMAPREDUCE_526346936_1</LEASEHOLDER>
+      <LEASEHOLDER>DFSClient_NONMAPREDUCE_240777107_1</LEASEHOLDER>
       <PATH>/hard-lease-recovery-test</PATH>
       <NEWHOLDER>HDFS_NameNode</NEWHOLDER>
     </DATA>
@@ -979,8 +979,8 @@
       <INODEID>0</INODEID>
       <PATH>/hard-lease-recovery-test</PATH>
       <REPLICATION>1</REPLICATION>
-      <MTIME>1421131351230</MTIME>
+      <MTIME>1421135812235</MTIME>
-      <ATIME>1421131349098</ATIME>
+      <ATIME>1421135810135</ATIME>
       <BLOCKSIZE>512</BLOCKSIZE>
       <CLIENT_NAME></CLIENT_NAME>
       <CLIENT_MACHINE></CLIENT_MACHINE>
@@ -991,7 +991,7 @@
         <GENSTAMP>1013</GENSTAMP>
       </BLOCK>
       <PERMISSION_STATUS>
-        <USERNAME>plamenjeliazkov</USERNAME>
+        <USERNAME>shv</USERNAME>
         <GROUPNAME>supergroup</GROUPNAME>
         <MODE>420</MODE>
       </PERMISSION_STATUS>
@@ -1002,13 +1002,13 @@
     <DATA>
       <TXID>76</TXID>
       <POOLNAME>pool1</POOLNAME>
-      <OWNERNAME>plamenjeliazkov</OWNERNAME>
+      <OWNERNAME>shv</OWNERNAME>
-      <GROUPNAME>staff</GROUPNAME>
+      <GROUPNAME>shv</GROUPNAME>
       <MODE>493</MODE>
       <LIMIT>9223372036854775807</LIMIT>
       <MAXRELATIVEEXPIRY>2305843009213693951</MAXRELATIVEEXPIRY>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>72</RPC_CALLID>
+      <RPC_CALLID>78</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1017,8 +1017,8 @@
       <TXID>77</TXID>
       <POOLNAME>pool1</POOLNAME>
       <LIMIT>99</LIMIT>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>73</RPC_CALLID>
+      <RPC_CALLID>79</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1029,9 +1029,9 @@
       <PATH>/path</PATH>
       <REPLICATION>1</REPLICATION>
       <POOL>pool1</POOL>
-      <EXPIRATION>2305844430345046085</EXPIRATION>
+      <EXPIRATION>2305844430349507141</EXPIRATION>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>74</RPC_CALLID>
+      <RPC_CALLID>80</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1040,8 +1040,8 @@
       <TXID>79</TXID>
       <ID>1</ID>
       <REPLICATION>2</REPLICATION>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>75</RPC_CALLID>
+      <RPC_CALLID>81</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1049,8 +1049,8 @@
     <DATA>
       <TXID>80</TXID>
       <ID>1</ID>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>76</RPC_CALLID>
+      <RPC_CALLID>82</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1058,8 +1058,8 @@
     <DATA>
       <TXID>81</TXID>
       <POOLNAME>pool1</POOLNAME>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>77</RPC_CALLID>
+      <RPC_CALLID>83</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1105,8 +1105,8 @@
         <NAME>a1</NAME>
         <VALUE>0x313233</VALUE>
       </XATTR>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>79</RPC_CALLID>
+      <RPC_CALLID>85</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1119,8 +1119,8 @@
         <NAME>a2</NAME>
         <VALUE>0x373839</VALUE>
       </XATTR>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>80</RPC_CALLID>
+      <RPC_CALLID>86</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
@@ -1132,22 +1132,22 @@
         <NAMESPACE>USER</NAMESPACE>
         <NAME>a2</NAME>
       </XATTR>
-      <RPC_CLIENTID>99bcddc1-3460-4630-9904-6c7ca5811945</RPC_CLIENTID>
+      <RPC_CLIENTID>cb20a92a-2c2f-4305-a838-2a01c6e73e18</RPC_CLIENTID>
-      <RPC_CALLID>81</RPC_CALLID>
+      <RPC_CALLID>87</RPC_CALLID>
     </DATA>
   </RECORD>
   <RECORD>
     <OPCODE>OP_ROLLING_UPGRADE_START</OPCODE>
     <DATA>
       <TXID>86</TXID>
-      <STARTTIME>1421131352186</STARTTIME>
+      <STARTTIME>1421135813268</STARTTIME>
     </DATA>
   </RECORD>
   <RECORD>
     <OPCODE>OP_ROLLING_UPGRADE_FINALIZE</OPCODE>
     <DATA>
       <TXID>87</TXID>
-      <FINALIZETIME>1421131352186</FINALIZETIME>
+      <FINALIZETIME>1421135813268</FINALIZETIME>
     </DATA>
   </RECORD>
   <RECORD>