1225164 - Sync one batch of most-recent history on first sync

Status: NEW

(Firefox for iOS :: Sync, defect)

Description

[Richard Newman [:rnewman]]

When we sync, we download all changed history.

On first sync, we download all history.

We used to do that in one request with a huge payload.

We now do that incrementally (Bug 1168856), but -- in order to work with the Sync protocol -- we do so from oldest to newest. If you have a lot of history on the server, this might mean that your most frecent sites don't arrive until we've grabbed 20+ batches.

We also keep syncing batches until we're done, so we block subsequent collections from syncing.

To address these two things, I propose:

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* If we haven't synced history before, grab a single batch, limit=100, newest-first, and don't track any metadata.

* Don't sync the rest of your history on first sync.

* Queue up another sync for 30 seconds after the first sync finishes.
--

I'll file another bug to think about big bookmark collections.