Slow to start after a refresh

[andybalaam]

Steps to reproduce

1. On develop.element.io, hit Refresh
2. See the "loading" screen for a long time

Outcome

What did you expect?

I expected Element Web to launch reasonably quickly.

What happened instead?

It takes 3 minutes or longer before I can see the room list, timeline, composer etc.

I think this got worse in the last few weeks, increasing from about 1 minute to much longer.

Operating system

Debian 12

Browser information

Firefox 140.0.4

URL for webapp

develop.element.io

Application version

Element version: 814f4a8-js-c2d25d937739 Crypto version: Rust SDK 0.13.0 (f64839e), Vodozemac 0.9.0

Homeserver

matrix.org

Will you send logs?

Yes

[andybalaam]

I rageshook and added a link to a Firefox profile of the startup process.

[andybalaam]

First glance observations:

We spend 22% of our time in OlmMachine::decrypt_room_event_inner, most of which is in Store::get_user_devices (these are Rust code running via WASM)