YARN Queue Manager UI behavior in mixed resource allocation mode

The mixed resource allocation mode in YARN is only supported through safety valves. If you open the Queue Manager UI or try to access Queue Manager APIs when mixed calculation mode is turned on, Queue Manager blocks the UI or APIs and informs you that mixed calculation mode is turned on, Queue Manager is inaccessible until this feature is fully compatible.

If the flag `yarn.scheduler.capacity.legacy-queue-mode.enabled` is not set or the property is missing, mixed resource allocation mode is not enabled in YARN. The detection of mixed allocation mode is determined by this flag in the capacity scheduler safety valve XML.

For more details on Mixed resource allocation, see the links provided below.

Scenarios

The following scenarios describe how the YARN Queue Manager UI behaves in mixed resource allocation mode in YARN.

• If YARN mixed resource allocation mode is activated or detected while the YARN Queue Manager is already running, it causes YARN Queue Manager UI to fail to load, resulting in an error message being displayed in the UI.

  

• If you start the YARN Queue Manager while YARN is already in mixed resource calculation mode, Queue Manager UI and APIs are blocked displaying the following error message.