[HDFS-9801] ReconfigurableBase should update the cached configuration

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.8.0
• Fix Version/s: 2.8.0, 3.0.0-alpha1
• Component/s: datanode
• Target Version/s: 2.9.0
• Hadoop Flags: Reviewed
• Assignee: Arpit Agarwal
• Reporter: Arpit Agarwal
• Created: 27/Jan/16 21:25
• Updated: 30/Aug/16 01:19
• Resolved: 12/Feb/16 20:44

Description

ReconfigurableBase#startReconfigurationTask does not update its cached configuration after a property is reconfigured. This means that configuration values queried via getConf().get(...) can be outdated. One way to fix it is ReconfigurableBase#reconfigurePropertyImpl returns the new effective value of the config setting and caller i.e. ReconfigurableBase will use it to update the configuration.

See discussion on HDFS-7035 for more background.