I am using Spring Integration with
mqtt-paho version 4.0.4 For receiving MQTT messages on specified topic.
When application is receiving huge load I found that, sometimes application is dropping connection with IMA (mqtt) and this was happened three times in a span of 1 Lac record.
But it regains the connectivity and started consuming messages received there after. There were no issue in IMA re-connectivity.
There is some other issue which I faced during this testing.
When there is continuous load on application, at some point application stops receiving messages and we can see one message flashed on screen i.e.
May 04, 2015 2:45:29 PM org.eclipse.paho.client.mqttv3.internal.ClientState checkForActivity
SEVERE: gvjIpONtSpP: Timed out as no activity, keepAlive=60,000 lastOutboundActivity=1,430,730,869,017 lastInboundActivity=1,430,730,929,151
After this we can see that there are no messages received on application even if continuous load is pushed through utility.
This behavior I found it three times.
At around 40K.
At around 90K.
At around 145K.
There is no consistent point or figures where application actually stops receiving messages.
Please let me know if anybody has faced and solved this before .
We had the same issue during performance testing and during MQTT Paho client performance/durability testing, before moving to production. The issue was on broker side, after settings adjustment, the IMA broker was able to consume millions of messages with no rejection.
Please look into max buffer parameter on IMA configuration web console. And overlimit behavior policy (what to do with messages published over specified threshold): reject, rollover etc.