Sliding Sync does not seem to work

[erebion]

Description

Release notes mention that Synapse 1.114.0 enabled Sliding Sync by default:

Enable native sliding sync support (matrix-org/matrix-spec-proposals#3575 and matrix-org/matrix-spec-proposals#4186) by default. (#17648)

I've upgraded Synapse and tried logging in with Element X.

It just tells me something like "This homeserver does not currently support SlidingSync.".

Steps to reproduce

• ugrade to 1.114.0
• try to log in using Sliding Sync
• Element X claims Sliding Sync is not suported.

Homeserver

erebion.eu

Synapse Version

1.114.0

Installation Method

Docker (matrixdotorg/synapse)

Database

Postgres, single container

Workers

Single process

Platform

Debian Stable

Configuration

No response

Relevant log output

There's nothing in the logs that I can find.

Anything else that would be useful to know?

No response

[YamatoRyou]

"Sliding Sync is enabled by default in Synapse 1.114.0" refers to "Simplified Sliding Sync"
Native Sliding Sync is disabled by default in Elemnet X (0.5.1, Android, iOS? I don't know). Your server needs to support Sliding Sync (proxy) in order to switch to native Sliding Sync later. This will cause your server to use both Sliding Sync implementations at the same time.

1. Visit https://github.com/matrix-org/sliding-sync and follow the instructions to run the Sliding Sync (proxy implementation) instance;
2. Log in to your server using Element X;
3. On the Element X settings page, click the version number 7 times in a row, then go to "Developer Options";
4. Find and enable "Simplified Sliding Sync";
5. Log in to your server again.

---

If you have a way to access the developer options before logging in, just do step 5.

[immanuelfodor]

It reads like the worst possible UX. You first need to have the Sliding Sync Proxy for not depending on it then?! 😅 I wanted to avoid installing the sliding sync proxy in the first place.

[erikjohnston]

Note that currently released versions of Element X do need the proxy, this is more to support the upcoming releases which won't require them. We may have jumped the gun slightly by sticking it at the top of the changelog!

[avsm]

Thanks for tha clarification @erikjohnston! I ran into the exact same problem as @immanuelfodor -- I'm excited to try Element X, but also can't install the sliding sync proxy. I guess I'll keep an eye out for future updates of Element X that will work without the proxy, now that my server's updated...

[SNThrailkill]

I was so excited to try out sliding sync and then I saw this issue. Is this now just waiting on the Element X side or is there more needed in the Synapse side like for auth?

[paboum]

Okay, so when is it going to be actually released and supported?

As in:

• https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html will describe the config
• https://github.com/matrix-org/sliding-sync will be bundled and configurable from Synapse's config file or replaced by native support
• Logs confirming that whatever (proxy or native) support is enabled on the instance and user may now test it
• Benchmarks and risks are also documented and provided to the homeserver admins so they can decide if want to use it
• No more "this is actually going to be supported in another release" apologetics

[avsm]

I've just upgraded to version 1.7.5 of Element X which was released on the App Store just now for Apple devices, and it's working great! Thank you to for all the hard work that went into this, Matrix devs :-) @erikjohnston

[paboum]

I see 6 open bugs with "sliding sync" in their names. So it's probably safe to say that sliding sync feature is now in beta tests phase and v1.115.0 will not be the final feature release. I would also love learn hw requirements for new instances with this feature (ideally, estimates for 10, 100, 1k, 10k users).