[HDDS-8187] ReplicationManager: Datanode commands should be sent to nodeManager directly

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Done
• Fix Version/s: 1.4.0
• Component/s: SCM
• Labels: pull-request-available
• Target Version/s: 1.4.0
• Assignee: Stephen O'Donnell
• Reporter: Stephen O'Donnell
• Created: 16/Mar/23 16:43
• Updated: 20/Mar/23 09:47
• Resolved: 20/Mar/23 09:47

Description

In order to keep a consistent count of the number of pending replicate and delete commands, ReplicationManager should send commands to the datanode via the nodeManager.addDatanodeCommand() method rather than publishing them to the event queue.

At the moment, the commands goto the event queue, where they are picked up by NodeManager and added to the datanode command queue. As we are using the counts in the command queue to determine how many commands are pending, the indirection provided by the event queue makes it difficult to keep a consistent count without excessive effort.

There is also no further processing done on the commands in the event queue, they simply go RM -> Event Queue -> Node Manager -> Command Queue.

This change makes RM send the commands to nodeManager directly.

Issue Links

• links to: GitHub Pull Request #4413