Re: [External] ActiveMQ-5.15.5 : InFlight showing negative number for Queue

[Matt Pavlovich <ma...@gmail.com>]

> On Apr 24, 2023, at 11:52 AM, Suresh, Subashree RTX <su...@rtx.com.INVALID> wrote:
> 
> Thanks Matt.  Have few questions though
> 
> 
>  1.  I see one of the queues dispatched is considerably higher than dequeueCount.   Could you explain little more about the issue and what might be the underlying causes after running without issues all these years?


Most likely caused by consumer applications using a prefetch (Default is 1000) and then closing before they acknowledge all messages that have been prefetched for them.

>  2.  My understanding, dequeued messages are already consumed by the consumers, dispatched are messages that are dequeued and inflight. How can we see if the messages are already prefetched and how does it cause to increase queue size??

Dispatched is the number of times a messages was sent inflight. So this covers resends to consumers.

>  3.  Does the bug exist in 5.15.5? Is it fixed only in 5.18.1? We are using activemq-5.17.2 in another application, should we switch that also too 5.18.1??

Most of the stats fixes were in later 5.15.x or 5.16.x. Going to 5.18.1 just gets you current to latest patches, no sense doing anything in-between.  5.15.x upgrades to 5.18.x really smooth. Just check the release notes. The only big change off the top of my head is that networkConnectors descreaseNetworkConsumers default value is now ’true’ instead of ‘false’.

Thanks,
Matt Pavlovich