Linux kernel has released a new asynchronous I/O APIs : io_uring and has added support for all network and disk I/O syscalls over last 1.5 year and it looks very promising.

Few of the other project has started adopting it and have seen performance benefits:

• Ceph: os/bluestore: introduce new io_uring IO engine ceph/ceph#27392
• Qemu: https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg06733.html

Many others frameworks like Netty are planning to adopt it too: https://twitter.com/normanmaurer/status/1257597649705893888

In context with the scale at which everyone runs clickhouse, I think it will be of great performance improvement.