[HDFS-6622] Rename and AddBlock may race and produce invalid edits

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 2.5.0
• Fix Version/s: 2.5.0
• Target Version/s: 2.5.0
• Assignee: Kihwal Lee
• Reporter: Kihwal Lee
• Created: 02/Jul/14 19:56
• Updated: 15/Aug/14 05:41
• Resolved: 10/Jul/14 04:07

Description

While investigating HDFS-6618, we have discovered that rename happening in the middle of getAdditionalBlock() can lead to logging of invalid edit entry.

In getAdditionalBlock() , the path is resolved once while holding the read lock and the same resolved path will be used in the edit log in the second half of the method holding the write lock. If a rename happens in between two locks, the path may no longer exist.

When replaying the AddBlockOp, it will fail with FileNotFound.