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Comment by Symmetry | Hacker News Reader

That's possible, but the Shield has a K1 varient with 4 32-bit A15 cores on the chip while the Nexus 9 has a varient of the K9 that has 2 64-bit Project Denver cores. The graphics are identical between the two versions of the K1 so I don't expect much difference in the GPU benchmarks, but I expect the CPU benchmark comparison to be interesting. On one hand we'll have four 3-wide conventional OoO cores. On the other we'll have two cores that are initially narrow and in order but are 7-wide VLIWs once the code morphing software has had a chance to run.

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Is that big little cores or four symmetric cores?

Four symmetric cores - all A15s. I don't think NVidia has ever done big.LITTLE even though they had a fifth core with the same architecture but different process/gate sizes for lower power in some previous Tegra chips. But you can see from them all having the same max frequency that all four cores are the same.

32-bit K1 also has the companion core[1] (probaly Cortex A7).

[1] http://www.extremetech.com/wp-content/uploads/2014/01/tegra-...

The companion core of the ARMv7 TK1 is a low power Cortex-A15, like the grandparent comment says. This is different from ARM's big.LITTLE which uses different microarchitectures for the two clusters, i.e. Cortex-A15 + Cortex-A7 or Cortex-A53 + Cortex-A57.

It's too small to be A15. I found the information that the companion core was A15 in Tegra 4, but it's similar size to other cores[1].

[1]http://cnet4.cbsistatic.com/hub/i/2013/01/06/318d69ea-fdb7-1...

Sorry, but that looks more like an artist's vision of a die shot than an actual die shot. The TRM is pretty clear that it's an A15: http://i.imgur.com/Fvh2KVT.png

Core size isn't just a matter of the number of gates, but also their size. One important tool for reaching high frequencies in chips is to have gates that drive more capacities load be wider and therefore higher power. But if your goal is to have an architecturally identical core that's lower power one of the tools you have to accomplish that is to not do that. There's probably other ways to shrink a core at the cost of performance, as well.

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