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1. Use kafka-configs.sh to set log.cleaner.threads=2, the client will send it to server using AdminClient.incrementalAlterConfigs(), the broker will merge the old snapshot( {} ) with delta and save the new snapshot( {log.cleaner.threads=2} ) to metadata storage.
2. Use kafka-configs.sh to set background.threads=1, the client will send it to server using AdminClient.incrementalAlterConfigs(), the broker will merge the old snapshot( {log.cleaner.threads=2} ) with delta and save got the new snapshot ({log.cleaner.threads=2, background.threads=1 }) to metadata storage.

Compatibility, Deprecation, and Migration Plan

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