[HDFS-14952] Skip safemode if blockTotal is 0 in new NN

• Type: Improvement
• Status: Resolved
• Priority: Trivial
• Resolution: Fixed
• Fix Version/s: 3.3.0, 3.1.4, 3.2.2, 2.10.1
• Component/s: namenode
• Labels: performance
• Assignee: Xiaoqiao He
• Reporter: Rajesh Balamohan
• Created: 04/Nov/19 14:58
• Updated: 09/Dec/19 20:03
• Resolved: 19/Nov/19 20:23

Description

When new NN is installed, it spends 30-45 seconds in Safemode. When blockTotal is 0, it should be possible to short circuit safemode check in BlockManagerSafeMode::areThresholdsMet.

https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManagerSafeMode.java#L571

Issue Links

• is related to: HDFS-11090 Leave safemode immediately if all blocks have reported in