commit fd0321d4e431ddb12116c6c213bce742033e18dc

Author: Hairong Kuang <hairong@ucdev21.inktomisearch.com>
Date:   Tue May 4 19:14:10 2010 +0000

    HDFS:1104 from https://issues.apache.org/jira/secure/attachment/12443523/fsckATime_Yahoo0.20.patch
    
    +++ b/YAHOO-CHANGES.txt
    +    HDFS-1104. Fsck triggers full GC on NameNode. (hairong)
    +


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20-security-patches@1077438 13f79535-47bb-0310-9956-ffa450edef68

src/hdfs/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -807,10 +807,6 @@ public class FSNamesystem implements FSConstants, FSNamesystemMBean {
    */
   LocatedBlocks getBlockLocations(String clientMachine, String src,
       long offset, long length) throws IOException {
-    if (isPermissionEnabled) {
-      checkPathAccess(src, FsAction.READ);
-    }
-
     LocatedBlocks blocks = getBlockLocations(src, offset, length, true);
     if (blocks != null) {
       //sort the blocks
@@ -838,6 +834,10 @@ public class FSNamesystem implements FSConstants, FSNamesystemMBean {
    */
   public LocatedBlocks getBlockLocations(String src, long offset, long length,
       boolean doAccessTime) throws IOException {
+    if (isPermissionEnabled) {
+      checkPathAccess(src, FsAction.READ);
+    }
+
     if (offset < 0) {
       throw new IOException("Negative offset is not supported. File: " + src );
     }

src/hdfs/org/apache/hadoop/hdfs/server/namenode/NameNode.java

@@ -445,6 +445,19 @@ public class NameNode implements ClientProtocol, DatanodeProtocol,
                                         src, offset, length);
   }
   
+  /**
+   * The specification of this method matches that of
+   * {@link getBlockLocations(Path)}
+   * except that it does not update the file's access time.
+   */
+  LocatedBlocks getBlockLocationsNoATime(String src, 
+                                         long offset, 
+                                         long length)
+      throws IOException {
+    myMetrics.numGetBlockLocations.inc();
+    return namesystem.getBlockLocations(src, offset, length, false);
+  }
+  
   private static String getClientMachine() {
     String clientMachine = Server.getRemoteAddress();
     if (clientMachine == null) {

src/hdfs/org/apache/hadoop/hdfs/server/namenode/NamenodeFsck.java

@@ -34,7 +34,6 @@ import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.protocol.Block;
-import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -83,7 +82,7 @@ public class NamenodeFsck {
   /** Delete corrupted files. */
   public static final int FIXING_DELETE = 2;
   
-  private final ClientProtocol namenode;
+  private final NameNode namenode;
   private final NetworkTopology networktopology;
   private final int totalDatanodes;
   private final short minReplication;
@@ -110,7 +109,7 @@ public class NamenodeFsck {
    * @param response the object into which  this servelet writes the url contents
    * @throws IOException
    */
-  NamenodeFsck(Configuration conf, ClientProtocol namenode,
+  NamenodeFsck(Configuration conf, NameNode namenode,
       NetworkTopology networktopology, 
       Map<String,String[]> pmap, PrintWriter out,
       int totalDatanodes, short minReplication) {
@@ -195,7 +194,7 @@ public class NamenodeFsck {
       return;
     }
     long fileLen = file.getLen();
-    LocatedBlocks blocks = namenode.getBlockLocations(path, 0, fileLen);
+    LocatedBlocks blocks = namenode.getBlockLocationsNoATime(path, 0, fileLen);
     if (blocks == null) { // the file is deleted
       return;
     }

src/test/org/apache/hadoop/hdfs/server/namenode/TestFsck.java

@@ -33,10 +33,12 @@ import junit.framework.TestCase;
 import org.apache.commons.logging.impl.Log4JLogger;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FSDataOutputStream;
+import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.DFSClient;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
@@ -73,12 +75,21 @@ public class TestFsck extends TestCase {
     FileSystem fs = null;
     try {
       Configuration conf = new Configuration();
+      final long precision = 1L;
+      conf.setLong("dfs.access.time.precision", precision);
       conf.setLong("dfs.blockreport.intervalMsec", 10000L);
       cluster = new MiniDFSCluster(conf, 4, true, null);
       fs = cluster.getFileSystem();
-      util.createFiles(fs, "/srcdat");
-      util.waitReplication(fs, "/srcdat", (short)3);
+      final String fileName = "/srcdat";
+      util.createFiles(fs, fileName);
+      util.waitReplication(fs, fileName, (short)3);
+      FileStatus[] stats = fs.listStatus(new Path(fileName));
+      assertFalse(0==stats.length);
+      final Path file = stats[0].getPath();
+      long aTime = fs.getFileStatus(file).getAccessTime();
+      Thread.sleep(2*precision);
       String outStr = runFsck(conf, 0, true, "/");
+      assertEquals(aTime, fs.getFileStatus(file).getAccessTime());
       assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));
       System.out.println(outStr);
       if (fs != null) {try{fs.close();} catch(Exception e){}}