HDFS-2975. Rename with overwrite flag true can make NameNode to stuck in safemode on NN (crash + restart). (Yi Liu via umamahesh)

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

@@ -680,6 +680,9 @@ Release 2.6.0 - UNRELEASED
 
       HDFS-6954. With crypto, no native lib systems are too verbose. (clamb via wang)
 
+      HDFS-2975. Rename with overwrite flag true can make NameNode to stuck in safemode 
+      on NN (crash + restart). (Yi Liu via umamahesh)
+
 Release 2.5.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES

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

@@ -452,7 +452,7 @@ boolean renameTo(String src, String dst, long mtime)
    * @see #unprotectedRenameTo(String, String, long, Options.Rename...)
    */
   void renameTo(String src, String dst, long mtime,
-      Options.Rename... options)
+      BlocksMapUpdateInfo collectedBlocks, Options.Rename... options)
       throws FileAlreadyExistsException, FileNotFoundException,
       ParentNotDirectoryException, QuotaExceededException,
       UnresolvedLinkException, IOException {
@@ -462,7 +462,7 @@ void renameTo(String src, String dst, long mtime,
     }
     writeLock();
     try {
-      if (unprotectedRenameTo(src, dst, mtime, options)) {
+      if (unprotectedRenameTo(src, dst, mtime, collectedBlocks, options)) {
         namesystem.incrDeletedFileCount(1);
       }
     } finally {
@@ -569,8 +569,9 @@ boolean unprotectedRenameTo(String src, String dst, long timestamp)
 
   /**
    * Rename src to dst.
-   * See {@link DistributedFileSystem#rename(Path, Path, Options.Rename...)}
-   * for details related to rename semantics and exceptions.
+   * <br>
+   * Note: This is to be used by {@link FSEditLog} only.
+   * <br>
    * 
    * @param src source path
    * @param dst destination path
@@ -581,6 +582,31 @@ boolean unprotectedRenameTo(String src, String dst, long timestamp,
       Options.Rename... options) throws FileAlreadyExistsException, 
       FileNotFoundException, ParentNotDirectoryException, 
       QuotaExceededException, UnresolvedLinkException, IOException {
+    BlocksMapUpdateInfo collectedBlocks = new BlocksMapUpdateInfo();
+    boolean ret = unprotectedRenameTo(src, dst, timestamp, 
+        collectedBlocks, options);
+    if (!collectedBlocks.getToDeleteList().isEmpty()) {
+      getFSNamesystem().removeBlocksAndUpdateSafemodeTotal(collectedBlocks);
+    }
+    return ret;
+  }
+  
+  /**
+   * Rename src to dst.
+   * See {@link DistributedFileSystem#rename(Path, Path, Options.Rename...)}
+   * for details related to rename semantics and exceptions.
+   * 
+   * @param src source path
+   * @param dst destination path
+   * @param timestamp modification time
+   * @param collectedBlocks blocks to be removed
+   * @param options Rename options
+   */
+  boolean unprotectedRenameTo(String src, String dst, long timestamp,
+      BlocksMapUpdateInfo collectedBlocks, Options.Rename... options) 
+      throws FileAlreadyExistsException, FileNotFoundException, 
+      ParentNotDirectoryException, QuotaExceededException, 
+      UnresolvedLinkException, IOException {
     assert hasWriteLock();
     boolean overwrite = options != null && Arrays.asList(options).contains
             (Rename.OVERWRITE);
@@ -670,7 +696,6 @@ boolean unprotectedRenameTo(String src, String dst, long timestamp,
         if (removedDst != null) {
           undoRemoveDst = false;
           if (removedNum > 0) {
-            BlocksMapUpdateInfo collectedBlocks = new BlocksMapUpdateInfo();
             List<INode> removedINodes = new ChunkedArrayList<INode>();
             if (!removedDst.isInLatestSnapshot(dstIIP.getLatestSnapshotId())) {
               removedDst.destroyAndCollectBlocks(collectedBlocks, removedINodes);
@@ -680,7 +705,7 @@ boolean unprotectedRenameTo(String src, String dst, long timestamp,
                   dstIIP.getLatestSnapshotId(), collectedBlocks, removedINodes,
                   true).get(Quota.NAMESPACE) >= 0;
             }
-            getFSNamesystem().removePathAndBlocks(src, collectedBlocks,
+            getFSNamesystem().removePathAndBlocks(src, null, 
                 removedINodes, false);
           }
         }

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

@@ -3627,12 +3627,14 @@ void renameTo(final String srcArg, final String dstArg,
     HdfsFileStatus resultingStat = null;
     boolean success = false;
     writeLock();
+    BlocksMapUpdateInfo collectedBlocks = new BlocksMapUpdateInfo();
     try {
       checkOperation(OperationCategory.WRITE);
       checkNameNodeSafeMode("Cannot rename " + src);
       src = resolvePath(src, srcComponents);
       dst = resolvePath(dst, dstComponents);
-      renameToInternal(pc, src, dst, cacheEntry != null, options);
+      renameToInternal(pc, src, dst, cacheEntry != null, 
+          collectedBlocks, options);
       resultingStat = getAuditFileInfo(dst, false);
       success = true;
     } finally {
@@ -3640,6 +3642,10 @@ void renameTo(final String srcArg, final String dstArg,
       RetryCache.setState(cacheEntry, success);
     }
     getEditLog().logSync();
+    if (!collectedBlocks.getToDeleteList().isEmpty()) {
+      removeBlocks(collectedBlocks);
+      collectedBlocks.clear();
+    }
     if (resultingStat != null) {
       StringBuilder cmd = new StringBuilder("rename options=");
       for (Rename option : options) {
@@ -3649,8 +3655,9 @@ void renameTo(final String srcArg, final String dstArg,
     }
   }
 
-  private void renameToInternal(FSPermissionChecker pc, String src, String dst,
-      boolean logRetryCache, Options.Rename... options) throws IOException {
+  private void renameToInternal(FSPermissionChecker pc, String src, 
+      String dst, boolean logRetryCache, BlocksMapUpdateInfo collectedBlocks, 
+      Options.Rename... options) throws IOException {
     assert hasWriteLock();
     if (isPermissionEnabled) {
       // Rename does not operates on link targets
@@ -3665,7 +3672,7 @@ private void renameToInternal(FSPermissionChecker pc, String src, String dst,
 
     waitForLoadingFSImage();
     long mtime = now();
-    dir.renameTo(src, dst, mtime, options);
+    dir.renameTo(src, dst, mtime, collectedBlocks, options);
     getEditLog().logRename(src, dst, mtime, logRetryCache, options);
   }
   

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

@@ -131,6 +131,7 @@ public void testRename() throws Exception {
   
   /**
    * Check the blocks of dst file are cleaned after rename with overwrite
+   * Restart NN to check the rename successfully
    */
   @Test(timeout = 120000)
   public void testRenameWithOverwrite() throws Exception {
@@ -160,6 +161,11 @@ public void testRenameWithOverwrite() throws Exception {
       dfs.rename(srcPath, dstPath, Rename.OVERWRITE);
       assertTrue(bm.getStoredBlock(lbs.getLocatedBlocks().get(0).getBlock().
           getLocalBlock()) == null);
+      
+      // Restart NN and check the rename successfully
+      cluster.restartNameNodes();
+      assertFalse(dfs.exists(srcPath));
+      assertTrue(dfs.exists(dstPath));
     } finally {
       if (dfs != null) {
         dfs.close();