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Interesting article with a lot of great historical context. I think a significant part of the tl;dr is that the end of Dennard Scaling and trouble with Moore's

Interesting article with a lot of great historical context. I think a significant part of the tl;dr is that the end of Dennard Scaling and trouble with Moore's law may mean that the best architecture will finally win out, rather than just the one with the best semiconductor design team behind it. I'm a bit skeptical of the promise of DSAs, though it does seem we're already going that way. Curious what others think on that point.

gbrown_ 8y ago
I agree, my concern is where do DSAs go in a few generations? How many efficiency/performance gains can be had before hitting the same limits hampering general purpose processors today?
- Symmetry 8y ago
  A DSA is only going to be an order of magnitude or two more performant than a general computer on any given process node. They'll certainly slow down at the same time general purpose CPUs slow down. The thing is it makes more sense to design and include them in a world where transistors are potentially getting cheaper without getting better because a finite amount of engineering effort will be stretched across a longer timeframe.
  - vanderZwan 8y ago
    Does that also imply a potential power savings of an order of magnitude or two? Because then it becomes a lot more obvious that the demand for them will be there in mobile phones and laptops at least.
    - Symmetry 8y ago
      Yes, it does. And that's a big part of the push for dedicated co-processors that we've seen in SoCs.
Symmetry 8y ago
The article didn't well on Dark Silicon but the idea is that as you can fit more structures on a chip but can't light up them all for power dissipation reasons it makes sense to include more and more specialized structures you only use for some purposes. With the rise of GPUs and specialized co-processor for things like media decoding and encryption we're certainly well on our way there. It would be nice to have an intermediate between the two in more places, like the Hexagon VLIW DSP that Qualcomm puts in its Snapdragon DSPs. And of course there are the even more specialized matrix convolution processors that everybody is designing and NVidia is now putting in its GPU. I think the real question is if it will make sense to have FPGAs in wider use. Certainly not until the programming model improves...

gbrown_ 8y ago

I agree, my concern is where do DSAs go in a few generations? How many efficiency/performance gains can be had before hitting the same limits hampering general purpose processors today?

Symmetry 8y ago
A DSA is only going to be an order of magnitude or two more performant than a general computer on any given process node. They'll certainly slow down at the same time general purpose CPUs slow down. The thing is it makes more sense to design and include them in a world where transistors are potentially getting cheaper without getting better because a finite amount of engineering effort will be stretched across a longer timeframe.
- vanderZwan 8y ago
  Does that also imply a potential power savings of an order of magnitude or two? Because then it becomes a lot more obvious that the demand for them will be there in mobile phones and laptops at least.
  - Symmetry 8y ago
    Yes, it does. And that's a big part of the push for dedicated co-processors that we've seen in SoCs.

Symmetry 8y ago

The article didn't well on Dark Silicon but the idea is that as you can fit more structures on a chip but can't light up them all for power dissipation reasons it makes sense to include more and more specialized structures you only use for some purposes. With the rise of GPUs and specialized co-processor for things like media decoding and encryption we're certainly well on our way there. It would be nice to have an intermediate between the two in more places, like the Hexagon VLIW DSP that Qualcomm puts in its Snapdragon DSPs. And of course there are the even more specialized matrix convolution processors that everybody is designing and NVidia is now putting in its GPU. I think the real question is if it will make sense to have FPGAs in wider use. Certainly not until the programming model improves...