libev_scheduler

libev_scheduler is a libev-based fiber scheduler for Ruby 3.0 based on code extracted from Polyphony.

Installing

$ gem install libev_scheduler

Usage

Fiber.set_scheduler Libev::Scheduler.new

Fiber.schedule do
  do_something_awesome
end

Also have a look at the included tests and examples.

The scheduler implementation

The present gem uses libev to provide a performant, cross-platform fiber scheduler implementation for Ruby 3.0. The bundled libev is version 4.33, which includes an (experimental) io_uring backend.

The Ruby fiber scheduler interface

The fiber scheduler interface is a new feature in Ruby 3.0, aimed at facilitating building fiber-based concurrent applications in Ruby. The current specification includes methods for:

• starting a non-blocking fiber
• waiting for an IO instance to become ready for reading or writing
• sleeping for a certain time duration
• waiting for a process to terminate
• otherwise pausing/resuming fibers (blocking/unblocking) for use with mutexes, condition variables, queues etc.

Here are some of my thoughts on this interface.