[HDFS-11409] DatanodeInfo getNetworkLocation and setNetworkLocation shoud use volatile instead of synchronized

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.9.0, 3.0.0-alpha4, 2.8.4
• Component/s: performance
• Hadoop Flags: Reviewed
• Assignee: Chen Liang
• Reporter: Chen Liang
• Created: 14/Feb/17 00:35
• Updated: 03/Apr/20 18:19
• Resolved: 14/Feb/17 21:03

Description

DatanodeInfo has synchronized methods getNetworkLocation and setNetworkLocation. While they doing nothing more than setting and getting variable location.

Since location is not being modified based on its current value and is independent from any other variables. This JIRA propose to remove synchronized methods but only make location volatile. Such that threads will not be blocked on get/setNetworkLocation.

Thanks szetszwo for the offline disscussion.

Issue Links

• is duplicated by: HDFS-5242 Reduce contention on DatanodeInfo instances