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Comment by nialv7 | Hacker News Reader

You were just ahead of your time :)

Multicore advantage for gaming is starting to materialize with Vulkan, mantle, etc.

Aren't Vulkan/Metal etc about GPUs rather than CPUs ?

Indeed, they are designed to reduce CPU load. Even so, if the game can't use multiple cores and previously was running game logic & OpenGL driver on the same core, now it's only the game logic. [1]

[1] nVidia actually implements Vulkan on top of their OpenGL driver, but nVidia's drivers have been relatively well optimized in terms of CPU usage already. AMD is the bigger winner here.

The OpenGL threading model is completely screwed up. You essentially have a global lock per GL context, which means you're restricted to 1 thread for issuing rendering. And in GL a context is for everything, including shaders, texture states, you can't even reasonable do uploads of new scene data in a separate thread.

Vulkan fixes this big time, by allowing apps to construct GPU workloads for a single GPU in parallel. Only the final submission step (which is supposed to be very low overhead if the driver design is decent) is single-threaded per GPU context. And even for that Vulkan is better: It allows you to allocate different contexts for separate engines (e.g. rendering vs. compute vs. copy engine for data up/download to/from the GPU vram).

The lower CPU overhead is just the icing on the cake, the real deal is that Vulkan fixed the threading/locking model.

Yes and no: here is a short article about it from Brad Wardell the CEO from Stardock [0]. Vulkan/Mantle/DirectX12 allow the game developer to really take advantage of multicore CPU's. Which is why we see the most gains with these new low level API's for AMD's FX chips because they are better at multi-threaded workloads compared to single threaded workloads like with previous DirectX versions.

A quote from the linked article:

  To to summarize:

  DirectX 11: Your CPU communicates to the GPU 1 core to 1 core at a time. It is still a big boost over DirectX 9 where only 1 dedicated thread was allowed to talk to the GPU but it’s still only scratching the surface.
  DirectX 12: Every core can talk to the GPU at the same time and, depending on the driver, I could theoretically start taking control and talking to all those cores.

  That’s basically the difference. Oversimplified to be sure but it’s why everyone is so excited about this.

[0] http://www.littletinyfrogs.com/article/460524/DirectX_11_vs_...

and current gen console ports forced to work smoothly on multiple anemic 1.6GHz cores

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