Delayed message consumption on composite queue targets

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Delayed message consumption on composite queue targets

TheQL
This post was updated on .
Hello,

I am watching some odd behaviour. We have defined a composite queue with two queue targets with two entirely different consumers on the target queues. Yet both consumers seem to consume these messages with the same delay. The queue message count graph looks entirely the same on both queues, piling up to the same high and then dropping back to zero. I am struggling to find a reason for this. There is no flow control or such.

There seems to be a general performance issue at the moment, other queues are also not empty which is the usual default status, but I cannot figure that one out either. There is no high load on the system or any other resource shortage. But maybe this is the reason for my findings and it is unrelated to the composite queue targets. It did come out of nothing though, no changes of any kind to the setup or the infrastructure occurred recently, so I thought I might just drop a question here, but I know it is vague to say the least.

It's a HA router running 9.6.0 on Java 6.

Addendum: I did notice a rising message count on one of the rt$ queues to a remotely connected router. This might just be because of the general performance, but could this also be a cause for decreasing performance? I am still talking about less than 400 messages, but anyway, the network bandwidth between the two routers can get pretty low from time to time, I am wondering if this could hit general performance or only messages that actually need to pass via the rt$ queue.
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Re: Delayed message consumption on composite queue targets

IIT Software
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I assume it's the flow control. For composite queues always the max flow control delay of both queues is returned. So if one consumer is slower than the other and hits the fc threshold, it returns a delay to the producer which is then throttled.
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Re: Delayed message consumption on composite queue targets

TheQL
As this occurred again today I was finally able to pin it down.

The issue was a little more complex, but in the end you were correct. The composite queue did not have much to do with that and what got me confused was the consumers not picking up any more messages that already were in the queue. The reason was active flow control on the rt$remoterouterX queue, which I believe kept the producer threads waiting while writing to remote target queues and since consume and produce is encapsuled within one transaction all threads were waiting and no more consumer threads were available.

Thanks for your help!
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Re: Delayed message consumption on composite queue targets

IIT Software
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Thanks for the update!
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