RightSpeed

RightSpeed is an experimental application server to host Rack applications, on Ractor workers, to test/verify that your application is Ractor-safe/Ractor-ready or not. Ractor is an experimental feature of Ruby 3.0, thus this application server is also not for production environments.

Currently, RightSpeed supports the very limited set of Rack protocol specifications. Unsupported features are, for example:

  • Writing logs into files
  • Daemonizing processes
  • Reloading applications without downtime
  • Handling session objects (using rack.session)
  • Handling multipart contents flexisbly (using rack.multipart.buffer_size nor rack.multipart.tempfile_factory)
  • Hijacking

Is Ractor-based server faster than prefork processes?

It can be. In our opinion, it may not be a tremendous difference, but could be a little improvement because:

  • Accepted connection delivery inter-Ractor should be faster than bringing those over IPC
  • JIT compilation can be just once using multiple Ractor
  • ... and?

Changelog

  • v0.2.0:
    • Add worker-type "fair" and "accept" in addition to "roundrobin"
  • v0.1.0:
    • The first release just before RubyKaigi Takeout 2021

Usage

Use the latest Ruby 3.x release!

Install right_speed by gem command (gem i right_speed), then use it directly:

$ right_speed -c config.ru -p 8080 --workers 8

# See right_speed --help for full options:
$ bundle exec ruby bin/right_speed --help
Usage: right_speed [options]

OPTIONS
  --config, -c PATH     The path of the rackup configuration file (default: config.ru)
  --port, -p PORT       The port number to listen (default: 8080)
  --backlog NUM         The number of backlog
  --workers NUM         The number of Ractors (default: CPU cores)
  --worker-type TYPE    The type of workers (available: roundrobin/fair/accept, default: roundrobin)
  --help                Show this message

Or, use rackup with -s right_speed:

$ rackup config.ru -s right_speed -p 8080 -O Workers=8

The default number of worker Ractors is the number of CPU cores.

Worker Types

The --worker-type option is to try some patterns of use of Ractors.

  • roundrobin
    • Listener Ractor will accept connections, then send those to Worker Ractors in round-robin
    • Worker Ractors will consume their input connections one-by-one
  • fair
    • Listener Ractor will accept connections, and yield those to consumers (workers)
    • Worker Ractors will take connections from Listener as soon as they become available
  • accept
    • Listener does nothing
    • Worker Ractors will accept connections, process requests individually

Currently, any of above workers cannot work well. We observed SEGV or Ruby runtime busy after traffic in seconds.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/tagomoris/right_speed.

License

The gem is available as open source under the terms of the MIT License.