We spent a lot of time on this comparison between @apachekafka, RabbitMQ, and Pulsar to make it thorough and fair. We used the standard Open Messaging Benchmark, with all code publicly available. I hope you find the article informative and insightful! https://www.confluent.io/blog/kafka-fastest-messaging-system/

If you want to learn more about design differences between the three systems, watch @benstopford’s and my talk at @kafkasummit on Mon Aug 24 @ 10am PT, with the tongue-in-cheek title “Trade-offs in Distributed Systems Design: Is @apachekafka The Best?".
http://events.kafka-summit.org/2020-schedule 

Fwiw our findings are corroborated by @TwitterEng, who migrated from a setup based on a BookKeeper derivative like Pulsar to @apachekafka (now powering 150M msgs/sec). An earlier write-up is https://blog.twitter.com/engineering/en_us/topics/insights/2018/twitters-kafka-adoption-story.html, and a new meetup talk will be on Sep 02 https://www.meetup.com/KafkaBayArea/events/272643868/