Is there a plan for batched subscriptions?

[faridsaid20]

In mqtt you can subscribe to array of topics in one request.
This can speed up the initial subscription phase when you need to subscribe to 5 or 10 or 100 topics in one request instead of running them separately.

I run some quick benchmarks and on my computer to subscribe to 2k topics with x6 CPU throttling takes:
1 500ms for zenoh-ts
300ms for mqtt ( batched )

This can be huge difference for embedded hardware with low cpu capabilities that run web applications.

You probably could add new method that has to have "key expressions" and "handlers"?

const handler = (sample) => console.log(sample)

declare_subscribers( [ { "key_expr1", handler }, { "key_expr2", handler } ] )

Or batch them behind the scenes yourselves without exposing new method like mqtt does by default for up to 3 subscriptions.

[milyin]

Hello @faridsaid20 ! Thank you for this report!
I think this issue is a part of more wide problem of ineffective protocol between zenoh-ts in browser and zenohd websocket plugin. There are plans to rework this protocol. Adding subscription batching behind the scenes (or may be explicit as some API extensiob) should be part of this update. Thank you again for noticing this!

[milyin]

There is "batching" API in zenoh-pico. It makes sense to use similar logic/naming in the TS API