public void updAllowedSetting(ClientMaster.ApprovedClientConfig allowedConfig) {
        if (allowedConfig != null) {
            if (configId.get() != allowedConfig.getConfigId()) {
                configId.set(allowedConfig.getConfigId());
            }
            if (allowedConfig.hasMaxMsgSize()
                    && allowedConfig.getMaxMsgSize() != defMaxMsgSize.get()) {
                defMaxMsgSize.set(SettingValidUtils.validAndGetMaxMsgSizeInB(
                        allowedConfig.getMaxMsgSize()));
            }
        }
    }
The class caches the max msg size settings
 returned from the server.
inlong-tubemq/tubemq-client/src/main/java/org/apache/inlong/tubemq/client/producer/MaxMsgSizeHolder.java