When a multi-node RabbitMQ cluster runs across multiple availability zones, all data transferred between nodes is charged at $0.01/GB. Google Cloud charges for outgoing traffic only. Amazon Web Services and Microsoft Azure charge for both incoming and outgoing traffic.
This is based on 1 Quorum Queue with 5 Producers and 5 Consumers, each with its own dedicated Connection and Channel. We use the c2-standard-8 GCP instance type, with 4 vCPUs and 10GB RAM dedicated to each RabbitMQ node. Each node has a 500GB SSD disk with max 15k read and write IOPS, and 240MB/s read and write throughput. Disk write throughput is the limiting factor, and the sliders on the left readjust to reflect this.