On June 27, Epic Games released Fortnite’s Playground Mode and for one brief moment it seemed like the entire Fortnite community descended on the game at the same time, all in the hope of trying out the highly anticipated mode. Unfortunately, under the weight of so many players trying to start games, Fortnite’s matchmaking system crumbled and Playground had to be taken down for a few days of maintenance. But after some server fixes, the mode returned a few days later, good as new.
While this explanation, and the actual release of the mode, sated most fans’ curiosity, Epic wasn’t satisfied. So, on Wednesday night, the company released a detailed explanation of what happened to Playground mode, Fortnite’s matchmaking system and how Epic fixed the problems.
The first thing Epic did in its post is explain what exactly the issue was when the mode was first released. The short version is something like this: Most Fortnite matches only have one match created for every 100 players online, but for Playground, Epic had to create between 25 and 100 times as many matches. That’s where the problems started.
While the company did have the server capacity to host all of those matches, what it didn’t have was the infrastructure to actually place each group of players into the proper server. The system simply couldn’t create matches and lobbies fast enough. This put a huge strain on the entire matchmaking system and eventually, the whole service fell over, taking out Playground Mode as well as all of the game’s other modes.
The first thing Epic did to fix this issue was isolate Playground Mode to make sure that even when the mode was fixed and back online, it wouldn’t have any effect on the other game modes’ queues. Next, Epic created a new system for its matchmaking service that allowed it to constantly shift resources between regions.
Match creation for Fortnite is handled in part by something called nodes, each of which have a list of available server spaces that matches can be placed into. One of the issues that the initial Playground launch ran into was running out of space on these nodes, which were having a hard time finding available server space and taking too long to do it because of the number of people searching.
In order to fix this, Epic created a system that would allow nodes from regions that aren’t currently running at capacity to shift regions to an area where nodes were in need of extra assistance. According to Epic, this was a complex solution to a difficult problem, but it worked, allowing the company to bring Playground mode back online as well as improve the matchmaking systems for the other game modes along the way.