webMethods

Hi,

I am new to Kafka implementation and using wM kafka adaper to consume messages from a Topic in Kafka(client side). What I noticed is, even if there are multiple messages present in topic, sometimes Listener/listnerNotification consumes 2 messages from the topic and sometimes 1 message at a time. On what criteria does a consumer fetch messages from Topic. Is there is any setting apart from Connection/Listner properties needs to be looked upon. Due to this behaviour there is issue coming in our code implementation. Below is snippet from server log:

Consumed {1} messages
AyncListenerNotification : runNotification() start
AsyncListenerNotification :: received msg count :1
Publishing for notification : started.
Publishing for notification : ended.
AyncListenerNotification : runNotification() end
Time taken to execute notifications in seconds:0

Consumed {2} messages
AyncListenerNotification : runNotification() start
AsyncListenerNotification :: received msg count :2
Publishing for notification : started.
Publishing for notification : ended.
AyncListenerNotification : runNotification() end
Time taken to execute notifications in seconds:0

Thanks & regards,
Garva

I have only played around with the Kafka adapter, and although I did not run into the issue you’re describing, I do understand that there is a property called max.poll.records that you can set to control how many messages get consumed at once. My understanding, however, is that this property is set to 500 by default so I don’t believe this property is the reason why you’re only getting one or two messages at a time. Nevertheless, you can try playing with it to see if has any impact.

This property is set in the adapter connection’s “Other Properties” field, e.g. max.poll.records=50

Hope this helps,
Percio

Thanks for response Percio. I will try setting the property as suggested and update the behavior.