By: Patrick Chase (patrickjchase.delete@this.gmail.com), May 19, 2013 11:38 am
Room: Moderated Discussions
David Kanter (dkanter.delete@this.realworldtech.com) on May 18, 2013 8:50 am wrote:
> But the fundamental problem illustrated by the above example is that frequency isn't
> an abstract quantity. Frequency @ power is a meaningful metric and I'd like to see
> more clear disclosure from the ARM-based vendors in particular. E.g., yes Tegra 4i
> can run at 2.3GHz, but with how many cores and at what power consumption in the CPU
> block and at the platform level? How does it look with 2 cores? With all 4
> cores? And how does power change as you sweep across different frequencies? How
> does the frequency change for different durations of workloads (e.g., how does it
> drop down over time)?
>
> I think if you were to really look at the complete picture here and start asking
> those questions, you'd really see that Apple, Intel and Qualcomm get significant
> benefits from their custom CPU cores (and process technology for Intel).
ARM offers a quad-core hard macro instatiation of the A15 for TSMC 28HPM. Assuming they did an equally good job of physical design then that would be roughly comparable to the custom designs you list above. http://www.arm.com/products/processors/hard-macro-processors.php.
That said, I think that Intel, Apple (Intrinsity/PAsemi), and Qualcomm have all proven to have *very* good design teams...
-- Patrick
> But the fundamental problem illustrated by the above example is that frequency isn't
> an abstract quantity. Frequency @ power is a meaningful metric and I'd like to see
> more clear disclosure from the ARM-based vendors in particular. E.g., yes Tegra 4i
> can run at 2.3GHz, but with how many cores and at what power consumption in the CPU
> block and at the platform level? How does it look with 2 cores? With all 4
> cores? And how does power change as you sweep across different frequencies? How
> does the frequency change for different durations of workloads (e.g., how does it
> drop down over time)?
>
> I think if you were to really look at the complete picture here and start asking
> those questions, you'd really see that Apple, Intel and Qualcomm get significant
> benefits from their custom CPU cores (and process technology for Intel).
ARM offers a quad-core hard macro instatiation of the A15 for TSMC 28HPM. Assuming they did an equally good job of physical design then that would be roughly comparable to the custom designs you list above. http://www.arm.com/products/processors/hard-macro-processors.php.
That said, I think that Intel, Apple (Intrinsity/PAsemi), and Qualcomm have all proven to have *very* good design teams...
-- Patrick