Guild Wars 2 is a game that rarely experiences downtime, even when major updates are deployed. That’s why it came as something of a shock — to players and ArenaNet employees alike — when the EU servers for the game went down in May of 2020. They came up and went down a few times over the course of a day, and at the time we had only a brief statement from ArenaNet to explain the problems.
Today, ArenaNet Platform Team Lead Robert Neckorcuk went into much greater detail about the circumstances surrounding that event in a post on the Guild Wars 2 site. It’s a long read, but here are the highlights:
GW2 uses two servers, a primary and a secondary, so that one can take over if something bad happens to the other. They frequently copy info between each other, to make sure all data is accounted for. Just before the weekend, ArenaNet upgraded its servers for the EU region, noting that data was writing slowly between them. They figured it would be fine and left for the weekend.
It wasn’t fine. On the morning of May 11, that speed of communication was dwarfed by the speed of new data being written and everything basically went to hell.
The culprit was the drivers for the server’s new operating system. When ArenaNet upgraded those, the write speed increased dramatically and the queue of backlogged messages disappeared “nigh instantly.” Problem solved! (Also, update your drivers, kiddos.)
Neckorcuk explained that several more measures have been put in place to watch for similar situations in the future. In the year-plus since the incident, Guild Wars 2 has had 99.98% uptime, with only five minor interruptions. All’s well that ends well, though not without some trauma, as Neckorcuk started his piece by saying, “I can assure you, I didn’t have to look up this date — it’s still a pretty vivid memory for me.” It’s OK, Robert, the bad date can’t hurt you any more.