[HDFS-6552] add DN storage to a BlockInfo will not replace the different storage from same DN

• Type: Bug
• Status: Closed
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 2.3.0, 2.4.0
• Fix Version/s: 2.5.0
• Component/s: namenode
• Target Version/s: 2.5.0
• Hadoop Flags: Reviewed
• Assignee: Amir Langer
• Reporter: Amir Langer
• Created: 17/Jun/14 07:51
• Updated: 04/Nov/14 07:13
• Resolved: 18/Jun/14 19:44

Description

In BlockInfo - addStorage code looks wrong.
At line 10 (below) - we remove the storage we're about to add from the list of storages, then add it.
If the aim was to replace the different storage that was there the line should have been:

removeStorage(getStorageInfo(idx));

method code:

1 boolean addStorage(DatanodeStorageInfo storage) {
2   boolean added = true;
3    int idx = findDatanode(storage.getDatanodeDescriptor());
4   if(idx >= 0) {
5      if (getStorageInfo(idx) == storage) { // the storage is already there
6        return false;
7      } else {
8        // The block is on the DN but belongs to a different storage.
9        // Update our state.
10        removeStorage(storage);
11        added = false;      // Just updating storage. Return false.
12     }
13  }
14  // find the last null node
15  int lastNode = ensureCapacity(1);
16  setStorageInfo(lastNode, storage);
17  setNext(lastNode, null);
18  setPrevious(lastNode, null);
19  return added;
20}