In NiFi queue with Load Balance Strategy RoundRobin flowfiles stuck

[#1]

Hi All

If in connection(queue between two processors)  I switch on RoundRobin strategy flow files start to stuck there for minutes. 

Some investigation showed, that flow files stuck only on the primary node.

No any Warns or Errors in logs.

I am ready to provide any information

Please, any help.

Thanks

[#2]

@MattWho Upgraded to Nifi 1.10 recently and flowfiles are struck with LoadBalance strategy PartitionBy Attribute

[#3]

@venu413 

Are these the same FlowFiles that were stuck prior to the upgrade? 
If you clean out your connections, do you see the issue occur later?

[#4]

@MattWho no these are not same flowfiles before upgrade.. 
We cleaned all flow files before upgrade...

[#5]

@JatinSab 

Troubleshooting this here with limited information is going to prove difficult.
Does the downstream processor of the connection with the "stuck" FlowFiles have...
1. Configured for all nodes or primary node Execution?  If primary node only, are the queued FlowFiles on the primary node?
2. Does processor show it has active threads?  (small number in upper right corner of processor) . If so, get some thread dumps from your NiFi and inspect if the thread is progressing or hung.
3. Is back pressure being applied on any of the outbound connections?
4. Is processor getting threads to do work?  What is CPU load on your system and configured "Max Timer Driven Thread Count?"  It may be set to low causing a thread starved situation for your dataflow.

Additionally, if you try to perform a "list queue" on the connection of issue, what result do you get?

If you have a support contract with Cloudera, you can open a support case and they can help you to a solution.

Thanks,

Matt