Matchmaker Update

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The server update today brought an adjustment to the matchmaking algorithm for the team queues.
The main goal was to enable people near the edges of the rating distribution to be matched with higher priority. This hopefully solves the problem that the very top and bottom players find it very hard or even impossible to find matches. At the same time we tried to further improve the quality of the resulting games with some other tweaks.
This means that the average difference between total ratings of the two teams in 4v4 should be about half of what we had previously. The rating differences between individual players should also be about half for most games. Very high level and low level games will probably not see much difference here. We should also be able to see more high level games.
This is all made possible with an average wait time increase of just 2-3 minutes.

We also lowered the matching timer to 90 seconds to make it less disheartening if you did not get matched in a round.

Speaking of matches, with the new algorithm it is expected that the number of waiting players will regularly exceed the number of theoretically required people for a game, sometimes by a lot. It is not a bug if nobody or just a few people get matched in such a situation! The algorithm requires a pool of people to be able to pick good matches. If the games possible with the current people are not good enough, the algorithm will wait for more people to show up, and if that doesn't happen it will reduce the quality threshold by a bit for those that are already waiting.
When there are many people in the queue that means that there will be low wait times, so don't be discouraged even if you don't get matched immediately.

Please leave feedback below. I am especially interested if the situation improved for high rated players.

There was a bug in that patch that inadvertently made it harder for very low and high rated players to get matched in team games. Yesterday we deployed a fix for this bug. It should now be significantly easier for those people to find games.

@blackyps said in Matchmaker Update:

There was a bug in that patch that inadvertently made it harder for very low and high rated players to get matched in team games. Yesterday we deployed a fix for this bug. It should now be significantly easier for those people to find games.

Nice!

Does this include the requested use of average team rating?

No the way maps are selected has not been changed. I think there should be client changes first to prepare for this change as outlined here: https://github.com/FAForever/downlords-faf-client/issues/2869

@blackyps said in Matchmaker Update:

The server update today brought an adjustment to the matchmaking algorithm for the team queues.
The main goal was to enable people near the edges of the rating distribution to be matched with higher priority. This hopefully solves the problem that the very top and bottom players find it very hard or even impossible to find matches. At the same time we tried to further improve the quality of the resulting games with some other tweaks.
This means that the average difference between total ratings of the two teams in 4v4 should be about half of what we had previously. The rating differences between individual players should also be about half for most games. Very high level and low level games will probably not see much difference here. We should also be able to see more high level games.
This is all made possible with an average wait time increase of just 2-3 minutes.

We also lowered the matching timer to 90 seconds to make it less disheartening if you did not get matched in a round.

Speaking of matches, with the new algorithm it is expected that the number of waiting players will regularly exceed the number of theoretically required people for a game, sometimes by a lot. It is not a bug if nobody or just a few people get matched in such a situation! The algorithm requires a pool of people to be able to pick good matches. If the games possible with the current people are not good enough, the algorithm will wait for more people to show up, and if that doesn't happen it will reduce the quality threshold by a bit for those that are already waiting.
When there are many people in the queue that means that there will be low wait times, so don't be discouraged even if you don't get matched immediately.

Please leave feedback below. I am especially interested if the situation improved for high rated players.

By the way, could you post up the github link for stuff like this? Trying to pin down where to look (I believe it is server?) to take a peek!

4c2446f9-7e97-4d8b-86f9-00c9031fdcc3-image.png

@morax yep that’s right

You mean the link to the release notes? I can do that

@blackyps said in Matchmaker Update:

You mean the link to the release notes? I can do that

Yup! I would like to actually read up on stuff rather speculate so when folks discuss things I can give an affirming nod.

Much appreciated!

Just to follow up on this - while I'm getting more games than previously (as I recall the improvement was quite significant!), high rating players are still being skipped very often for average 1800 games in favor of 1200s. Just one example: 091c1101-9435-4645-8eee-9ad944948f76-image.png I was skipped from this game (my rating is 2400). I get that it sounds a bit self centered that I should be getting a game instead of a 1100-1300, but 1. it's very rare for a game to launch that I can match with (as opposed to 1100-1300 who should have relatively little difficulty) and 2. I think it's safe to assume that 1800-2100 rated players would rather play with a 2400 than a 1100-1300.

@Blodir I suspect this game happened because there was no one else near your rating searching.

Including you in this game likely would have increased both the rating range inside one team and across teams.

I suspect if there was some 1500 also in queue it would have put you in. But without that it just wasn't a good match based on the metrics and likely everyone else had been in queue long enough it gave them the game.

671e9236-2050-47b6-aced-239c6e198134-image.png
Some more...

You do realize that you with your over 2400 rating obviously fit the least in this game, right?
b0153b23-54e4-40dc-9acc-449d1b154b4c-grafik.png

According to the server logs the other game was a premade team of four against two teams of two (ergodic with BalanceSlaveNoob and Tron- with Moi_Count).

@blackyps said in Matchmaker Update:

You do realize that you with your over 2400 rating obviously fit the least in this game, right?
b0153b23-54e4-40dc-9acc-449d1b154b4c-grafik.png

Yes. Again I understand that I may sound entitled, but I think the two points I mentioned earlier apply: players generally prefer to play with higher rating players in my experience, and someone at 2400 rating is less likely to find a game than someone at 1900 rating (though it's tough for those guys too!).

Also keep in mind that it's literally impossible for me to find a game with equally skilled players since there's literally not enough 2.4k players in the game to fill an 8 player game even if the highest rated players happened to magically play all at once. Ie. I "fit in the least" in every single game I play regardless of the players (actually I guess if we had yudi farms pepsi and me in a game it might be theoretically be possible to have a game where half of the players are 2400+ but the chances are pretty miniscule). If you only considered trying to minimize the rating diff between the players in the game then 2400+ players would be cut out of the match whenever possible since they are at the border of the rating range in every match.

Anyways just offering feedback from high rating perspective. Maybe I'm on too much copium, but I genuinely believe preferential matching of high rating players is better for FAF as a whole and not just to satisfy my selfish needs. I also think there's an argument to be made that it is more fair when you consider the reality of matching times. Also again I want to say that matching times are a lot better than before december, so thanks.

Please leave feedback below. I am especially interested if the situation improved for high rated players.

While we are at it I will also mention that there are quite a lot of games with a random 1200-1300 thrown in:
9190e5ce-c4d5-4a20-9016-a8e0d8189397-image.png
fda1ca3a-29bd-4fb0-8441-7e9626da6f54-image.png
There are several players at the top end that feel this way. I don't know how much can realistically be done to improve the situation in TMM and I understand that I'm asking for some pretty specific fine tuning, however we used to get 1800+ custom games regularly (can probably still get them tbh!) even if the wait times were a bit longer, and I think a lot of people preferred that. Again, talking about a miniscule part of the playerbase, but to a certain extent I think high rating players cause a domino effect on other tmm players (if 2200+ stops playing tmm, then 2000+ becomes the new 2200+ and they may stop playing too and so on) so it's not all about just a small minority whining.

@blodir said in Matchmaker Update:

Just to follow up on this - while I'm getting more games than previously (as I recall the improvement was quite significant!), high rating players are still being skipped very often for average 1800 games in favor of 1200s. Just one example: 091c1101-9435-4645-8eee-9ad944948f76-image.png

This one is different. All players queued up solo and choosing you instead of LittleRock would indeed be the better game according to matchmaker metrics. Nobody there gets any newbie bonuses and the wait times have been low as well. So it should have matched you instead. I have one possible explanation why it did in fact not put you into this game.
The matchmaker doesn't try out every possible combination of search parties. That is computationally too expensive. Instead it creates candidates by picking other searches with a similar rating until it has 8 players in total and then splits them into teams. It creates one candidate game for each search party. It is possible that the candidate games that contained you were not great so they got discarded and the theoretical good game that I mentioned was not in these candidate games at all, so the matchmaker was unaware of this solution.

EDIT
I just realized that I did my tests on an outdated server version. We capped the minority bonus later. What happened here is that there are so many high rated players in this game already that they already max out the minority bonus. So it doesn't prefer you anymore over any other player in this game. You being in the game instead of the 1116 makes the game slightly worse on paper, so the matchmaker chose the game without you instead.
The cap was introduced here: https://github.com/FAForever/server/pull/941

High rated players already get preferential matching, that's why the situation improved in december. In fact the preferential matching is the reason you get these random 1200s in your games. If you had 1000 rating you would have games that barely ever have more than 800 rating difference between players (assuming no premades). We could lower the bonus for high rated players again, but then we would at the same time increase the problem that you get left out of games.

I think we have reached a local optimum in matchmaker configuration and I feel unable to improve it further. It's just the reality of FAF that there is only a handful of top rated player and they stretch over like 300 rating. There are too few possible games to bridge the divide between too few matches and too unbalanced matches. There is no technical solution to this, or at least I can't see it. The only real fix I see is to coordinate with Yudi, farms, etc. to join the queue as well. As you said it's a feedback loop.

@blackyps

Why not increase the high-rated minority bonus with increasing rating (so that, for example, a 2.4k being in a match would yield a higher bonus than a 2k)?

pfp credit to gieb

That's what I am gonna do: https://github.com/FAForever/server/pull/957
It was probably a bit confusing because I made my edit to the first post after the second post, which made it look like I didn't want to fix the bug. But when the bug is fixed we are back to the state that I described in my second post. Maybe we are lucky and the situation is then satisfactory for everyone, but if it isn't then my statement holds again that I have no further ideas how to improve the situation.

The server update has been deployed, high rated players should now notice that the rating range in their game has decreased and consequently it is a bit harder for them to find games.