It's no secret that large PC releases have run into innumerable performance issues over the past few years, many of which leverage Unreal Engine. Even with the proliferation of Unreal Engine 5, games like Silent Hill 2, Oblivion Remastered, and Remnant II have shown major performance issues at release. Epic, developer of Unreal Engine, is recognizing the problem and says it has plans to address the performance limitations we've seen across dozens of PC ports in the next major version of its game engine, Unreal Engine 6.

Unreal Engine 6 wants to solve PC performance woes

Just don't expect to see any UE6 games any time soon

Appearing on the Lex Fridman podcast, Epic CEO Tim Sweeney spoke candidly about the state of Unreal Engine 5 and the issues Epic wants to tackle in Unreal Engine 6. The issue Sweeney points to is singled-threaded simulations. One of the biggest issues with Unreal Engine 4 and 5 is how it scales on heavily-threaded desktop CPUs like the Ryzen 9 9950X3D. Both engines largely rely on two threads: a game simulation thread and a render thread. With one thread handling all the simulation, you'll see stutters in games like Stars Wars Jedi: Survivor as the CPU struggles to keep up with the GPU.

Sweeney knows this is a problem: "The biggest limitation that's built up over time is the single-threaded nature of game simulation on Unreal Engine. We run a single-threaded simulation. If you have a 16-core CPU, we're using one core for game simulation and running the rest of the complicated game logic," Sweeney said. Although other game engines take a similar approach, we've seen games much better optimized for high-core count CPUs over the last few years. Cyberpunk 2077 and REDEngine are probably the best examples of that, with the game easily scaling up to accommodate 16-core chips.

In the next version of Unreal Engine, Sweeney says the team is specifically focused on optimizing the engine for a larger thread count. "We're really thinking about and working on the next generation of technology, and that being Unreal Engine 6, that's the generation we're actually going to go and address a number of the core limitations that have been with us over the history of Unreal Engine and get those on a better foundation that the modern world deserves, given everything that's been learned in the field of computing in that timeframe," Sweeney said.

Although it's great to hear that Epic recognizes the limitations of Unreal Engine, that doesn't mean we'll see a solution soon. Sweeney estimates that the first preview builds of Unreal Engine 6 will be available in two to three years, but the executive didn't commit to that timeframe. Even an optimistic estimate would put the first UE6 games sometime in 2028 or later.