Could you (Kafka/pulsar) devs add more details about low latency guarantees? With an in memory solution it is easier to talk about 99.9 or even more messages be

Could you (Kafka/pulsar) devs add more details about low latency guarantees? With an in memory solution it is easier to talk about 99.9 or even more messages below 10ms latency. Also this requires a client side push protocol (like redis subscribe). Assuming there are no slow consumers involved is there a configuration that guarantees 10-20ms latency? At what percentile?