Building scalable breakout rooms with Node.js worker threads

NodeJS worker threads have opened doors to many exciting implementations and functionalities on the server-side. Multiplayer networked games, and live engagement and collaboration, among others, make a really good candidate for CPU intensive applications which would greatly benefit from this multi-threaded-ness of NodeJS.

In this talk, we’ll understand everything about NodeJS worker threads and see a real implementation of this concept to simulate dedicated server instances to enable various groups of players to play private instances of a live quiz simultaneously.

Transcript

1. BUILDING SCALABLE BREAKOUT ROOMS USING NODE.JS WORKER THREADS Srushtika Neelakantam Developer Relations Engineer at Ably Realtime
2. HELLO! I’M SRUSHTIKA DevRel Engineer @Srushtika
3. Let’s see breakout rooms in action TIME FOR A FUN QUIZ! 3 @Srushtika | Brighton Web Dev Meetup | https://quiz.ably.dev/
4. BREAKOUT ROOMS FUNCTIONALITY 1. How does realtime messaging work? 2. How to make use of Node.js worker threads to efficiently simulate dedicated server instances for each breakout room? @Srushtika | Brighton Web Dev Meetup |
5. HTTP WebSockets vs. @Srushtika | Brighton Web Dev Meetup |
6. Publish/Subscribe messaging pattern Feature add-ons • Presence • Message History • Integrations . . . Infrastructure add-ons • Auto reconnection • Scale • Guaranteed delivery • Message ordering . . . P.S. This is an old gif, Ably has moved on to new branding now. @Srushtika | Brighton Web Dev Meetup |
7. BREAKOUT ROOMS FUNCTIONALITY 1. How does realtime messaging work? ✅ 2. How to make use of Node.js worker threads to efficiently simulate dedicated server instances for each breakout room? @Srushtika | Brighton Web Dev Meetup |
8. WORKER THREADS IN NODE.JS @Srushtika | Brighton Web Dev Meetup |
9. HOW DOES NODE.JS WORK? @Srushtika | Brighton Web Dev Meetup |
10. KEY ELEMENTS THAT MAKE NODE.JS WORK The chrome v8 engine converts JavaScript to machine readable code The libuv library provides and manages the event loop and thread pool @Srushtika | Brighton Web Dev Meetup |
11. GREAT EXPLANATION OF EVENT LOOP BY PHILIP ROBERTS (JSConfEU on YouTube) @Srushtika | Brighton Web Dev Meetup |
12. “Node.js is a CPU bottleneck due to its single-threaded nature. That’s one of its major drawbacks” @Srushtika | Brighton Web Dev Meetup |
13. WORKER THREADS IN NODE.JS @Srushtika | Brighton Web Dev Meetup |
14. NODE.JS WORKER THREADS ARCHITECTURE @Srushtika | Brighton Web Dev Meetup | Image source: The NodeSource Blog
15. @Srushtika | Brighton Web Dev Meetup |
16. Let’s see some real code https://github.com/ably-labs/realtime-quiz-framework @Srushtika | Brighton Web Dev Meetup |
17. BREAKOUT ROOMS FUNCTIONALITY 1. How does realtime messaging work? ✅ 2. How to make use of Node.js worker threads to efficiently simulate dedicated server instances for each breakout room? ✅ @Srushtika | Brighton Web Dev Meetup |
18. CAVEATS AND OTHER THINGS - Don’t use Worker threads for parallelizing I/O operations, the native Node architecture can do that more quickly - Creating worker threads is not cheap, so it’s better to create and use a thread pool instead - If there are async methods available, it’s better to use them, rather than off-loading to your own worker thread @Srushtika | Brighton Web Dev Meetup |
19. Thankyou! @Srushtika | Brighton Web Dev Meetup | Further reading - NodeJS docs: https://nodejs.org/api/worker_threads.html - Demo source code: https://github.com/Srushtika/realtime-quiz-framework - “What the heck is an event loop anyway?”: https://youtu.be/8aGhZQkoFbQ - “Introduction to libuv: What's a Unicorn Velociraptor?”: https://youtu.be/_c51fcXRLGw - Realtime concepts: https://ably.com/topics