Matchmaking event of type MatchmakingSucceeded did not contain player session ids of new incoming players

Can you provide matchmaking ticket ids and I can get the GameLift service team to investigate?

Yes, here are the tickets associated with the event:

b1bb51c1-d0b0-4ed2-b060-7ed3fc362fd9 a4a94c8e-7823-4b91-a029-3e8401d968b7 2f8c501a-c424-428b-a1be-5475e3b54278

Thanks I've opened an issue with the GameLift team.

I recently noticed this issue too. Players that leave the session or time out are still reported in backfill messages but don't have a player session.

Is this still going to be expected behavior or will this be changing somehow?

@REDACTEDUSER

Seems strange to have player data without a player session id on a game session update. As you mention that this is impacting players who've left / timed out on connect, this may due to the fact that your game server is currently responsible for updating the player data in this circumstance and I wonder if there is stale data being sent with the request.

I can confirm that what @REDACTEDUSER

@REDACTEDUSER

Hey @REDACTEDUSER

bc459d6a-08a0-4506-b97d-6001bbe1f0b4

I believe what happened exactly was that there was a situation in which a player left the game, and a backfill request was made with the remaining players. Then, one of the remaining players also left but the backfill request in progress was not cancelled. Therefore, players could get matched with this backfill ticket that was not truly representative of the players still in the game.

I don't know if this is necessarily good or bad behavior, since I found a way around this by cancelling backfill requests whenever players leave the game. In my case, I terminate the player session when a player leaves, so eventually a new backfill request gets made with the remaining players in the game.

I looked into what happened to that ticket. It was exactly like what you described. The player session was already completed by the time the match was formed.

FlexMatch assumes the players in match making tickets are accurate, so it currently records this abnormal case and returns a ticket with missing player session IDs.

Your method of canceling the backfill request when players leave the game is the right approach.