Cephalocon 2019

Seastar framework brings a new abstraction level over event-driven programming. It is by nature shared-nothing and non-block, hiding asynchronous functions behind its futures and continuations. That’s where the Crimson Project initiated, to liberate Ceph code from complex callbacks and rethink the design of performance from bottom up.

As the base of all other Ceph components which dispatch messages and connected as a cluster, Messenger is very performance-sensitive and also self-contained — a perfect start point for the redesign and validation works in Crimson. Although the new messenger is still under construction, facing challenges with the new programing paradigm and to be really efficient, still plenty can be shared and discussed, including Yingxin's gotchas during his implementations and Jianpeng's performance tests against the existing async-messenger.