1409111 - Sync could perform all get requests for a single batch in parallel.

Status: NEW

(Firefox :: Sync, enhancement, P3)

Description

[Thom Chiovoloni [:tcsc] (ex-moco)]

I don't know if changing this is *actually* a good idea, but at the moment, Desktop sync waits after each request it makes here[0]. We actually don't need to do this, we could just keep making requests, and just Promise.all them at the end.

I think this would be a pretty easy change and could make first syncs (esp. history) take materially less time, and be slightly more likely to succeed, less time taken would mean less chance of XIUS failing.

[0]: http://searchfox.org/mozilla-central/rev/40b456626e2d0409b7034768b4d9526fc7235ea4/services/sync/modules/record.js#740

Comment 1

[Thom Chiovoloni [:tcsc] (ex-moco)]

Actually I lied, this wouldn't be pretty easy, since it's not safe to issue two get()'s at the same time for one Resource object, because Reasons. There's probably a bug somewhere about making sync use `fetch` to do more of the HTTP gruntwork, but at the moment I can't locate it. We'd want to do that first, though.

Comment 2

[Mark Hammond (PTO; back Oct-3) [:markh] [:mhammond]]

Changing the description as I thought it was describing something quite different :)

While this probably does make sense, another consideration is that we might end up saturating low bandwidth connections, making the user's general browsing experience poor?