理论上，您可以使用来自jsr223测试元素的kafka客户机使用者代码从jmeter本身获得kafka主题中的挂起消息数
示例代码：

KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
consumer.subscribe(Collections.singletonList("test"));
while(true) {
    ConsumerRecords<String, String> records = consumer.poll(100);
    for (ConsumerRecord<String, String> record : records) {
        System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());

        // after each message, query the number of messages of the topic
        Set<TopicPartition> partitions = consumer.assignment();
        Map<TopicPartition, Long> offsets = consumer.endOffsets(partitions);
        for(TopicPartition partition : offsets.keySet()) {
            System.out.printf("partition %s is at %d\n", partition.topic(), offsets.get(partition));
        }
    }
}

这些值可以使用 vars 速记和打印到jmeter html报表 Jmeter 板作为自定义图表。