[mobile] sort user games by finished timestamp about lila HOT 10 OPEN

The current sort is also the one used on the website profile page game section: https://lichess.org/@/thibault/all

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Yes but on website it include all the games even the ongoing ones. So you can't really change the sort order.

But as explained, on the app it only shows the finished games, so here it makes sense to have a different sort order, doesn't it?

from lila.

I understand. The problem is that we have almost 9 billion games in the DB.

Adding a new sort order requires adding a new index, on the pair [userId, updatedAt]. The index would use 210GB on the prod DB server. And more later as the collection grows.

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I guess that lila-search should be able to solve this. as it stores last move timestamp.

from lila.

I see. So it would not be an issue if the website would use the same, by last update order.

In my opinion that order would also be better for the website. But I'd understand if you don't want to bother with that change.

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Oh and I considered only the game list. Maybe this index has other usages making the other order incompatible?

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You bet. Lots of usages.

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Maybe a separate tab for just correspondence games would help.

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I have an issue to implement filters on the app repo.
Filtering by perf would be the way to go imo, if possible.

See: lichess-org/mobile#454

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I don't think mongodb can handle it, so that would need to hit elasticsearch.

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