diff --git a/src/main/scala/app/CreateRepositoryServlet.scala b/src/main/scala/app/CreateRepositoryServlet.scala
index ef25436..42fede5 100644
--- a/src/main/scala/app/CreateRepositoryServlet.scala
+++ b/src/main/scala/app/CreateRepositoryServlet.scala
@@ -61,9 +61,6 @@
       FileUtils.deleteDirectory(tmpdir)
     }
     
-    // update all branches
-    updateAllBranches(LoginUser, form.name)
-    
     // redirect to the repository
     redirect("/%s/%s".format(LoginUser, form.name))
   }
diff --git a/src/main/scala/app/GitRepositoryServlet.scala b/src/main/scala/app/GitRepositoryServlet.scala
index 8fecbe2..2294e56 100644
--- a/src/main/scala/app/GitRepositoryServlet.scala
+++ b/src/main/scala/app/GitRepositoryServlet.scala
@@ -36,22 +36,4 @@
     });
   }
   
-  /**
-   * Override GitServlet#service() to pull pushed changes to cloned repositories for branch exploring.
-   */
-  override def service(request: HttpServletRequest, response: HttpServletResponse): Unit = {
-    super.service(request, response)
-    
-    logger.debug(request.getMethod + ": " + request.getRequestURI)
-    
-    // update branches
-    if(request.getMethod == "POST" && request.getRequestURI.endsWith("/git-receive-pack")){
-      request.getRequestURI
-          .replaceFirst("^" + request.getServletContext.getContextPath + "/git/", "")
-          .replaceFirst("\\.git/git-receive-pack$", "").split("/") match {
-        case Array(owner, repository) => Directory.updateAllBranches(owner, repository)
-      }
-    }
-  }
-  
 }
diff --git a/src/main/scala/app/RepositoryViewerServlet.scala b/src/main/scala/app/RepositoryViewerServlet.scala
index 26d2806..65ee7ab 100644
--- a/src/main/scala/app/RepositoryViewerServlet.scala
+++ b/src/main/scala/app/RepositoryViewerServlet.scala
@@ -98,57 +98,38 @@
     val raw        = params.get("raw").getOrElse("false").toBoolean
     val path       = multiParams("splat").head.replaceFirst("^tree/.+?/", "")
     val repositoryInfo = JGitUtil.getRepositoryInfo(owner, repository, servletContext)
-    
-    if(repositoryInfo.branchList.contains(id)){
-      // id is branch name
-      val dir  = getBranchDir(owner, repository, id)
-      val git  = Git.open(dir)
-      val rev  = git.log.addPath(path).call.iterator.next
-      val file = new File(dir, path)
+
+    val git = Git.open(getRepositoryDir(owner, repository))
+    val commitId = git.getRepository.resolve(id)
       
-      if(raw){
-        // Download
-        contentType = "application/octet-stream"
-        file
-      } else {
-        // Viewer
-        val viewer  = if(FileTypeUtil.isImage(file.getName)) "image" else if(FileTypeUtil.isLarge(file.length)) "large" else "text"
-        val content = ContentInfo(
-            viewer, if(viewer == "text") Some(FileUtils.readFileToString(file, "UTF-8")) else None
-        )
-        html.blob(id, repositoryInfo, path.split("/").toList, content, new CommitInfo(rev))
-      }
+    val revWalk = new RevWalk(git.getRepository)
+    val revCommit = revWalk.parseCommit(commitId)
+    revWalk.dispose
+      
+    @scala.annotation.tailrec
+    def getPathObjectId(path: String, walk: TreeWalk): ObjectId = walk.next match {
+      case true if(walk.getPathString == path) => walk.getObjectId(0)
+      case true => getPathObjectId(path, walk)
+    }
+      
+    val treeWalk = new TreeWalk(git.getRepository)
+    treeWalk.addTree(revCommit.getTree)
+    treeWalk.setRecursive(true)
+    val objectId = getPathObjectId(path, treeWalk)
+    treeWalk.release
+      
+    if(raw){
+      // Download
+      contentType = "application/octet-stream"
+      JGitUtil.getContent(git, objectId, false)
+        
     } else {
-      // id is commit id
-      val branch = JGitUtil.getBranchNameFromCommitId(id, repositoryInfo)
-      val dir    = getBranchDir(owner, repository, branch)
-      val git    = Git.open(dir)
-      val rev    = git.log.add(ObjectId.fromString(id)).call.iterator.next
-      
-      @scala.annotation.tailrec
-      def getPathObjectId(path: String, walk: TreeWalk): ObjectId = walk.next match {
-        case true if(walk.getPathString == path) => walk.getObjectId(0)
-        case true => getPathObjectId(path, walk)
-      }
-      
-      val walk = new TreeWalk(git.getRepository)
-      walk.addTree(rev.getTree)
-      walk.setRecursive(true)
-      val objectId = getPathObjectId(path, walk)
-      
-      if(raw){
-        // Download
-        contentType = "application/octet-stream"
-        JGitUtil.getContent(git, objectId, false)
+      // Viewer
+      val large   = FileTypeUtil.isLarge(git.getRepository.getObjectDatabase.open(objectId).getSize)
+      val viewer  = if(FileTypeUtil.isImage(path)) "image" else if(large) "large" else "text"
+      val content = ContentInfo(viewer, if(viewer == "text") JGitUtil.getContent(git, objectId, false).map(new String(_, "UTF-8")) else None)
         
-      } else {
-        // Viewer
-        val large   = FileTypeUtil.isLarge(git.getRepository.getObjectDatabase.open(objectId).getSize)
-        val viewer  = if(FileTypeUtil.isImage(path)) "image" else if(large) "large" else "text"
-        val content = ContentInfo(viewer, if(viewer == "text") JGitUtil.getContent(git, objectId, false).map(new String(_, "UTF-8")) else None)
-        
-        html.blob(branch, repositoryInfo, path.split("/").toList, content, new CommitInfo(rev))
-      }
+      html.blob(id, repositoryInfo, path.split("/").toList, content, new CommitInfo(revCommit))
     }
   }
   
@@ -162,18 +143,23 @@
     
     val repositoryInfo = JGitUtil.getRepositoryInfo(owner, repository, servletContext)
     
-    // get branch by commit id
-    // TODO this does not work correctly...
-    val branch = repositoryInfo.branchList.find { branch =>
-      val git = Git.open(getBranchDir(owner, repository, branch))
-      git.log.add(ObjectId.fromString(id)).call.iterator.hasNext
-    }.get
+    val git = Git.open(getRepositoryDir(owner, repository))
     
-    val dir = getBranchDir(owner, repository, branch)
-    val git = Git.open(dir)
-    val ite = git.log.add(ObjectId.fromString(id)).call.iterator
-    val rev = ite.next
-    val old = ite.next
+    @scala.annotation.tailrec
+    def getCommitLog(i: java.util.Iterator[RevCommit], logs: List[RevCommit]): List[RevCommit] =
+      i.hasNext match {
+        case true if(logs.size < 2) => getCommitLog(i, logs :+ i.next)
+        case _ => logs
+      }
+    
+    val revWalk = new RevWalk(git.getRepository)
+    revWalk.markStart(revWalk.parseCommit(git.getRepository.resolve(id)))
+    
+    val commits = getCommitLog(revWalk.iterator, Nil)
+    revWalk.release
+    
+    val rev = commits(0)
+    val old = commits(1)
     
     val diffs = if(old != null){
       // get diff between specified commit and its previous commit
@@ -204,7 +190,7 @@
       buffer.toList
     }
     
-    html.commit(branch, 
+    html.commit(id, 
         CommitInfo(rev.getName, rev.getCommitterIdent.getWhen, rev.getCommitterIdent.getName, rev.getFullMessage), 
         repositoryInfo, diffs)
   }
@@ -231,6 +217,7 @@
     val revWalk = new RevWalk(git.getRepository)
     val objectId = git.getRepository.resolve(revision)
     val revCommit = revWalk.parseCommit(objectId)
+    revWalk.dispose
     
     val files = JGitUtil.getFileList(owner, repository, revision, path)
     
diff --git a/src/main/scala/util/Directory.scala b/src/main/scala/util/Directory.scala
index 7cbe3fe..57a4613 100644
--- a/src/main/scala/util/Directory.scala
+++ b/src/main/scala/util/Directory.scala
@@ -32,46 +32,11 @@
     new File("%s/%s/%s.git".format(RepositoryHome, owner, repository))
   
   /**
-   * Temporary directory which is used in the repository viewer.
-   */
-  def getBranchDir(owner: String, repository: String, branch: String): File =
-    new File("%s/tmp/%s/branches/%s/%s".format(GitBucketHome, owner, repository, branch))
-  
-  /**
    * Temporary directory which is used in the repository creation.
    * GiyBucket generates initial repository contents in this directory and push them.
    * This directory is removed after the repository creation.
    */
   def getInitRepositoryDir(owner: String, repository: String): File =
     new File("%s/tmp/%s/init-%s".format(GitBucketHome, owner, repository))
-
-  def updateAllBranches(owner: String, repository: String): Unit = {
-    // TODO debug log
-    println("[pull]" + owner + "/" + repository)
-    
-    val dir = Directory.getRepositoryDir(owner, repository)
-    val git = Git.open(dir)
-    
-    val branchList = git.branchList.call.toArray.map { ref =>
-      ref.asInstanceOf[Ref].getName
-    }.toList
-    
-    branchList.foreach { branch =>
-      val branchName = branch.replaceFirst("^refs/heads/", "")
-      val branchdir = Directory.getBranchDir(owner, repository, branchName)
-      if(!branchdir.exists){
-        branchdir.mkdirs()
-        Git.cloneRepository
-          .setURI(dir.toURL.toString)
-          .setBranch(branch)
-          .setDirectory(branchdir)
-          .call
-        Git.open(branchdir).checkout.setName(branchName).call
-      } else {
-        Git.open(branchdir).pull.call
-      }
-    }
-  }
-
   
 }
\ No newline at end of file
diff --git a/src/main/scala/util/JGitUtil.scala b/src/main/scala/util/JGitUtil.scala
index 876c412..bd8c050 100644
--- a/src/main/scala/util/JGitUtil.scala
+++ b/src/main/scala/util/JGitUtil.scala
@@ -44,16 +44,6 @@
   }
   
   /**
-   * Get the branch name from the commit id.
-   */
-  def getBranchNameFromCommitId(id: String, repositoryInfo: RepositoryInfo): String = {
-      repositoryInfo.branchList.find { branch =>
-        val git = Git.open(getBranchDir(repositoryInfo.owner, repositoryInfo.name, branch))
-        git.log.add(ObjectId.fromString(id)).call.iterator.hasNext
-      }.get
-  }
-  
-  /**
    * Returns the file list of the specified path.
    * 
    * @param owner the repository owner