diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/git/LockFailureException.java b/gerrit-server/src/main/java/com/google/gerrit/server/git/LockFailureException.java
new file mode 100644
index 0000000000..7380b0a686
--- /dev/null
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/git/LockFailureException.java
@@ -0,0 +1,26 @@
+// Copyright (C) 2016 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.git;
+
+import java.io.IOException;
+
+/** Thrown when updating a ref in Git fails with LOCK_FAILURE. */
+public class LockFailureException extends IOException {
+  private static final long serialVersionUID = 1L;
+
+  public LockFailureException(String message) {
+    super(message);
+  }
+}
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/git/VersionedMetaData.java b/gerrit-server/src/main/java/com/google/gerrit/server/git/VersionedMetaData.java
index 6334cd2a8a..f7752dcf7c 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/git/VersionedMetaData.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/git/VersionedMetaData.java
@@ -347,9 +347,11 @@ public abstract class VersionedMetaData {
           case FORCED:
             update.fireGitRefUpdatedEvent(ru);
             return;
+          case LOCK_FAILURE:
+            throw new LockFailureException("Cannot delete " + ru.getName()
+                + " in " + db.getDirectory() + ": " + ru.getResult());
           case FAST_FORWARD:
           case IO_FAILURE:
-          case LOCK_FAILURE:
           case NEW:
           case NOT_ATTEMPTED:
           case NO_CHANGE:
@@ -424,9 +426,11 @@ public abstract class VersionedMetaData {
             revision = rw.parseCommit(ru.getNewObjectId());
             update.fireGitRefUpdatedEvent(ru);
             return revision;
+          case LOCK_FAILURE:
+            throw new LockFailureException("Cannot update " + ru.getName()
+                + " in " + db.getDirectory() + ": " + ru.getResult());
           case FORCED:
           case IO_FAILURE:
-          case LOCK_FAILURE:
           case NOT_ATTEMPTED:
           case NO_CHANGE:
           case REJECTED: