EventEngine production readiness

[Aleh Linkin]

Hello. Is EventEngine ready for production. Does it have any benefits before old implementation? I mean using default grpc engine not custom io library

[Adam Heller]

Hi Aleh,

The EventEngine has been used in production for most things on most platforms for a few releases. There are a couple of areas we're still working to migrate, but the majority of gRPC uses EventEngine functionality.

Besides the ability for applications to define and control their own event loops, communication layers, and async execution strategies, the EventEngine brings a thread pool into gRPC, which improves the Callback API (applications no longer need to "donate" threads). Internally, this migration will also allow us to open source a few things we've wanted to release for a while, such as allowing custom load balancing policies. That will be possible when the EventEngine is fully landed, maybe EOY. And the EventEngine eliminates a large chunk of tech debt, but not terribly apparent to external users.

Best,

-Adam