Problem Statement

When a consumer joins a consumer group and it can take more than 3 or more seconds to start consuming.

 

Solution

This is because the corresponding coordinator will wait for a given period before starting rebalancing the members when a new member appears. The period is controlled by the cluster configuration group_initial_rebalance_delay, which is set to 3 seconds by default.

 

If you want to change it, run the following command:

 

# Check the current value
rpk cluster config get group_initial_rebalance_delay

# Change it to a desired value
rpk cluster config set group_initial_rebalance_delay 

# Check if it applies correctly
rpk cluster config get group_initial_rebalance_delay

Notes

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