If you run RabbitMQ on RHEL9 family hosts (CentOS Stream 9, RockyLinux 9, AlmaLinux 9) and you see 1.6GB memory use then consider limiting amount of file descriptors:

EL9 (both CentOS Stream 9 and Rocky Linux 9) have 1073741816 while CentOS Stream 8 has 1048576 - after lowering it's acceptable memory usage.

https://github.com/rabbitmq/erlang-rpm/discussions/104 for more