With 8 Cards, Wolfenstein Ray Traced 7.7x Faster

An anonymous reader writes "As Slashdot readers know Intel's research project on ray tracing for games has recently been shown at 1080p, using eight Knights Ferry cards with Intel's 'Many Integrated Core' architecture. Now a white paper goes into more detail, documenting near-linear scaling for the cloud setup with 8 cards, and gives details on the implementation of 'smart anti-aliasing.' It will be interesting to see how many instances of Intel's next MIC iteration — dubbed Knights Corner, with 50+ cores — will be required for the same workload."

Comments

intel 3d

[maestroX]

so, how does it stack up against a Riva TNT2?
(ducks)

Re:Nice scaling

[subreality]

Note that these are raytracing cards, not rendering. Raytracing is a very different technique which can do cool effects like refraction through glass (shown in the chandeliers and scopes), jawdropping water, and realistic lighting effects that rendering cards simply cannot do.

It's also much more demanding on hardware. One of the big drawbacks is it requires a lot of scattered reads out of memory making caching much less effective. You need tons of bandwidth to low latency memory to make it happen. We're still a very long ways out from having this possible in reasonably-priced consumer GPUs.

Rag on Intel for their integrated graphics if you want (though I consider them a good non-gaming graphics chip with very good open source support), but these cards are not related to those in any way. These are full-featured x86/x64 processors with 32 cores per die. In other words, they created a 256-core system capable of software-raytracing the whole thing at high resolutions.

That is quite an accomplishment, and rest assured, it is top-tier performance in the raytracing world. This isn't meant to be a practical gaming system; this is pretty clearly being done by Intel to show off the benefits of their many-cores processors, and it is an impressive show.

To the GP: They're using Wolfenstein because it's one of very few games that has a ray-traced variant, and it exists only because Intel created it as a testbed. More on that here: https://en.wikipedia.org/wiki/Wolfenstein:_Ray_Traced

Re:Nice scaling

[root_42]

The problem with these demos is, they use ray tracing like we did in 1980 (i.e. Whitted style). All computations are highly coherent and efficient. As soon as you want to have more natural rendering, with diffuse illumination etc. Parellization doesn't scale proportionally anymore. Rays become heavily incoherent, memory access scatters and you get cache misses etc. So the real feat would have been if tey show 7.7x speed with diffuse global illumination.