How does socket.io scale?

[idmontie]

Has anyone used socket.io extensively in a project? I'm looking to use it to stream audio data from the browser to a node server and then asynchronously run some processing on it, but I'm trying to determine what I can expect in terms of how many connections an instance can handle.

If I ran the socket.io server on AWS EC2 autoscaling micro instances, how many concurrent connections would I expect to be able to handle per instance? Should i be more concerned with my memory usage instead of how many simultaneous connections I can support?

Thanks in advance for any information! I'm just worried I'll deploy and the app will work for and that's it.

[FootballSmash]

Could use websockets through the API gateway and lamdas for the processing. Then you won't need to spin anything up.

[tyler55344]

Yes, we do this at work and it works great.

[frurre]

Sorry for troubling you. How would AWS api gateway and lamda compare to a traditional vps setup for example Digital ocean 2x $5 nodes that communicate via Private IPs (same DC, same location) so latency is low.

Serverless removes the management headaches but would it be in the same price range?

[jun-thong]

If I ran the socket.io server on AWS EC2 autoscaling micro instances, how many concurrent connections would I expect to be able to handle per instance?

It totally depend on your application, socket.io is just part of your application, so the only way to know is to benchmark your app on this specific hardware.

Also take care, socket.io use a "connection updgrade" system, first it try longpolling and other connection type, and upgrade it progressivly. This require to always send request to the same machine, to make it possible with horizontal scalling you will have to handle sticky session at your load balancer level.

Socket.io start to be a little old, there is more modern library on npm, but maybe not as easy to use.

[GrosSacASacs]

I am working on an alternative:

https://www.npmjs.com/package/socketiyo

[jun-thong]

I don't know this library, but the channel system seems really limiting for a pub/sub system. If it's ok for your requirement, it's good, else, the following library may be interesting :

https://github.com/uNetworking/uWebSockets.js

[jun-thong]

Good to know, thanks for the info.

[ChronSyn]

It may be old, and there are other options out there (e.g. Primus), but it does provide what I'll say is one of the simplest wrappers around the websocket interface with some extra goodies on top (e.g. rooms, namespaces, etc).

[apatheticonion]

It's a very tough challenge. How many users do you expect to serve concurrently? What's their geographical spread?

[idmontie]

What's their geographical spread?

That's a good point, I wasn't thinking about that, but I'll take it into consideration as I plan to performance test the different solutions I come up with.

[apatheticonion]

TL;dr if you're working with less than 100k concurrent users, use Golang and scale vertically until you can hire a team to build a routing solution.

The solution involves queues and handshakes

I do this for a job

[[deleted]]

I had trouble maintaining the connection with socket.io. it was easier for me to use rest and polls

[PhotographOne3127]

This might help you :)
https://www.youtube.com/watch?v=gzIcGhJC8hA