Valorant's 128-Tick Servers

Summary

Hi, I’m Brent “Brentmeister” Randall and I’m an engineer on the Gameplay Integrity team for VALORANT. My team is responsible for VALORANT’s build system, automation framework, game client performance, and server performance. In this article, I’ll be focusing on that last topic - I’ll be telling the technical story behind our search for optimal server performance. From very early on in development, we knew that VALORANT would have very strict server performance requirements. I hope I can give you some insight into why that is, and how we accomplished our ambitious goals. When we started, a server frame took 50ms, and by the end we reached sub-2ms per frame - all by looking at code optimization, hardware tweaks, and OS tunings. Let’s go on a journey together. The Importance of Netcode All online shooters (even VALORANT) have some amount of peeker’s advantage. We’ve done a video blog on netcode and peeker’s advantage, and a previous Tech Blog article on the same. To provide a short summary - in VALORANT, a key part of the gameplay is taking strategic positions and holding them. Holding positions can become impossible if other players can run around a corner and kill the defender before the defender can react due to latency. That latency is partly based on the network and partly based on the server tick rate. To give defenders the time they need to react to aggressors, we determined that VALORANT would require 128-tick servers. If you’re interested in how we came to that conclusion, our tech blog post on peeker’s advantage covers it in detail. Code Optimization When we think about hosting servers at a 128-tick rate, our biggest constraint is CPU resources. We need to be able to process an entire frame within 7.8125ms, but if we do that, a single game would take up an entire CPU core! This diagram demonstrates how many games we can run per core: Utilizing 1 full core per game would make it prohibitively expensive to host our game servers at scale, considering we knew we ...