Scenario
You cannot directly modify an existing RocketMQ topic. The configuration information of a topic affects the transmission and consumption of messages. If you modify the topic directly, problems may occur for sending and consuming messages.
However, you may need to modify the topic configuration in the following scenarios:
l Adding partitions for a topic: When a topic has to process more messages, the original partitions may not be satisfying. You can add partitions for the topic. This way, you can improve the concurrent processing of messages and load balancing performance.
l Modifying the production mode of the topic: The production mode determines the mode and policy for sending messages. If you modify it directly, problems may occur for sending and consuming messages.
l Modifying the read-write permissions of the topic: Check the configuration of consumers and producers to ensure that they can read and write the messages of the topic correctly.
l Modifying topic remarks: You need to modify the topic remarks to cater to service requirements.
After modification, problems may occur for sending and consuming messages. Carefully evaluate and test it to ensure that there is no irreversible impact on the message system before you start the modification. You are advised to plan and configure a topic carefully based on service requirements when creating a topic to avoid frequent modification subsequently.
Procedure
1. Go to the topic management menu. Click Modify in the topic list.
2. You cannot modify the cluster, broker, or name of a topic. You can modify the number of partitions, production mode, read-write permission, and remarks.