[YARN-4898] Avoid sending NODE_LABELS_UPDATE event to scheduler when node label is not configured

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: resourcemanager
• Assignee: Unassigned
• Reporter: Rohith Sharma K S
• Created: 30/Mar/16 08:06
• Updated: 06/Apr/16 05:02

Description

It is observed that when ever new NodeManager is registered or expired with ResourceManager, a new additional event NODE_LABELS_UPDATE has been triggered even though Node Label is not enabled. This makes dispatcher to process one event without any real use.

logs : where all 100 of node-labels-update events processed by dispatcher.

2016-03-30 15:42:24,461 DEBUG [AsyncDispatcher event handler] event.AsyncDispatcher (AsyncDispatcher.java:dispatch(175)) - Dispatching the event org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.NodeLabelsUpdateSchedulerEvent.EventType: NODE_LABELS_UPDATE
2016-03-30 15:42:24,461 DEBUG [AsyncDispatcher event handler] event.AsyncDispatcher (AsyncDispatcher.java:dispatch(175)) - Dispatching the event org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.NodeLabelsUpdateSchedulerEvent.EventType: NODE_LABELS_UPDATE
2016-03-30 15:42:24,462 DEBUG [AsyncDispatcher event handler] event.AsyncDispatcher (AsyncDispatcher.java:dispatch(175)) - Dispatching the event org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.NodeLabelsUpdateSchedulerEvent.EventType: NODE_LABELS_UPDATE
2016-03-30 15:42:24,462 DEBUG [AsyncDispatcher event handler] event.AsyncDispatcher (AsyncDispatcher.java:dispatch(175)) - Dispatching the event org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.NodeLabelsUpdateSchedulerEvent.EventType: NODE_LABELS_UPDATE

Point of concern is In large cluster, it is seen that registering thousands of nodes altogether to running cluster might/would cause other events processing to get delayed.