[HDFS-8676] Delayed rolling upgrade finalization can cause heartbeat expiration and write failures

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 2.8.0, 2.7.2, 3.0.0-alpha1
• Target Version/s: 2.7.2, 2.6.5
• Hadoop Flags: Reviewed
• Assignee: Walter Su
• Reporter: Kihwal Lee
• Created: 26/Jun/15 16:32
• Updated: 06/Jan/17 00:51
• Resolved: 13/Oct/15 18:26

Description

In big busy clusters where the deletion rate is also high, a lot of blocks can pile up in the datanode trash directories until an upgrade is finalized. When it is finally finalized, the deletion of trash is done in the service actor thread's context synchronously. This blocks the heartbeat and can cause heartbeat expiration.

We have seen a namenode losing hundreds of nodes after a delayed upgrade finalization. The deletion of trash directories should be made asynchronous.

Issue Links

• depends upon: HDFS-7645 Rolling upgrade is restoring blocks from trash multiple times