[HIVE-20797] Print Number of Locks Acquired

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 4.0.0
• Fix Version/s: 4.0.0-alpha-1
• Component/s: HiveServer2, Locking
• Labels: newbie noob
• Assignee: David Mollitor
• Reporter: David Mollitor
• Created: 24/Oct/18 14:09
• Updated: 17/Nov/22 08:55
• Resolved: 07/Feb/19 12:22

Description

The number of locks acquired by a query can greatly influence the performance and stability of the system, especially for ZK locks. Please add INFO level logging with the number of locks each query obtains.

Log here:
https://github.com/apache/hive/blob/3963c729fabf90009cb67d277d40fe5913936358/ql/src/java/org/apache/hadoop/hive/ql/Driver.java#L1670-L1672

A list of acquired locks will be stored in the org.apache.hadoop.hive.ql.Context object and can be retrieved via org.apache.hadoop.hive.ql.Context#getHiveLocks.

https://github.com/apache/hive/blob/758ff449099065a84c46d63f9418201c8a6731b1/ql/src/java/org/apache/hadoop/hive/ql/lockmgr/HiveTxnManager.java#L115-L127