Sync is timing out when I log in with a user who has many rooms

[chagai95]

Steps to reproduce

1. Log in with a user with many rooms.

Outcome

What did you expect?

The sync should work

What happened instead?

It did not work.

Operating system

Ubuntu

Browser information

Chrome Version 100.0.4896.127 (Official Build) (64-bit)

URL for webapp

https://element.chagai.website/

Application version

1.10.8

Homeserver

Https://mx.chagai.website

Will you send logs?

Yes

[t3chguy]

A timeout would be an issue on the server side rather than the client, no?

[chagai95]

I was thinking maybe it could wait longer if it is setting the timeout, is it not?

matrix-org/synapse#12971

[t3chguy]

The underlying http library will be timing out based on whether the server is sending keepalives. Element will keep retrying sync, in theory the server should continue the operation in the background and eventually respond to one of the newer requests.

Is the timeout variable set from Element? Maybe it needs to be higher?

This is not the same thing. Please refer to the spec.
https://spec.matrix.org/v1.2/client-server-api/#get_matrixclientv3sync

The maximum time to wait, in milliseconds, before returning this request. If no events (or other data) become available before this time elapses, the server will return a response with empty fields.

This only applies if there is no data to send, i.e the long-polling effect.

[chagai95]

ok thanks! I saw the 504 and thought it's an error...

[t3chguy]

A 504 is an error, it is the (reverse) proxy timing out before the application does. /sync timeouts result in an empty response as per the spec. It'd be a 200, not a 504.

If no events (or other data) become available before this time elapses, the server will return a response with empty fields.

[chagai95]

ah ok thx for explaining!