[NIFI-11289] NiFi UI blocks on read access to FlowFile Queues

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0-M1, 1.21.0
• Component/s: Core Framework
• Assignee: Mark Payne
• Reporter: Mark Payne
• Created: 15/Mar/23 16:31
• Updated: 29/Mar/23 16:03
• Resolved: 15/Mar/23 20:32

Description

When the NiFi UI makes a request for a given Process Group or its status, the backend must obtain Read Locks on the FlowFile Queues in order to provide the information back to the UI.

This results in a sluggish UI whenever there are a lot of queues with a lot of FlowFiles flowing. And in a case where we drop huge numbers of FlowFiles or add huge numbers of FlowFiles to queue (for instance, as a result of SplitJson) that lock can be held for quite a while, making the UI block arbitrarily long.

The Read Locks, however, are not necessary for any of the requests that the UI makes for the canvas. They are necessary only for the Status History of the Connection/Queue. And for backward compatibility we should also make it available to Reporting Tasks.

Issue Links

• fixes: NIFI-10238 Priority queues may return incorrect status when flowfiles have just been migrated from swap to active
• links to: GitHub Pull Request #7046