Can't have that MBA beating the base spec MBP... -_-
But they probably still advertise "latest Intel CPU with xyz GHz and blah blah amount of cores.". But that would be like buying a Ferrari with advertised "an engine capable of gazillion horsepowers", but having it limited to only be able to go up to 2000 RPM...
From what I have seen of LTT, their biggest criticism of Apple is their tendency to emphasize the turbo boost clock speed when the CPU is nearly always being throttled (presumably below the base clock speed) due to the machine being unable to dissipate the heat.
If you want to see an example of Apple advertising the turbo boost speed in very large print, check out the "Overview" page on the 13" MacBook Pro.
I wonder how much faster the 13" Pro would be if they did a similar setup.
The only reason I can think of that Apple set up the MacBook Air like that was because it was supposed to be fanless and at the last second they couldn't figure out a way to eek out performance, so they added a fan where it would fit. That doesn't sound much like Apple's engineering though, so I don't know why they did it.
0: https://www.ifixit.com/Teardown/MacBook+Pro+13-Inch+Two+Thun...
A combination of good cooling + a tweaked power management profile to accommodate the better thermals should give a substantial performance increase.
Give it a try and report back.
edit: Wow, HN has changed. There was a time when experimentation was encouraged here.
You can see in the video how hot the CPU runs. If I remember correctly, a 20°C temperature increase halves the lifetime of electronics. "Normal" laptops tend to stick around 60°C-70°C. Apple apparently decided that halving or even quartering the CPU lifetime compared to that is fine.
That said, most MBA CPUs probably spend their CPU lifetime closer to idle. It'd be interesting to get temperature numbers for that. Still, it's worse than it could - and IMHO should - be.
The entire overclocking community would disagree with you.
Modifying the thermal & power management profile is very difficult as it would require reverse-engineering the firmware.
I guess a temporary hack would be to mess with the current sensing circuitry to make the machine believe the CPU is drawing less current that it actually is and encourage it to give it more power.
Would this be in the OS or the bios (or whatever they call it on a Mac)?
If it's the former, I wonder if the test would have been more interesting if the MBA was running a different OS.
Doing it within the operating system is suicidal as a malfunction of the OS (whether accidental or due to malware) would force the machine to operate beyond its thermal limits and potentially damage itself.
There's also multiple levels of protection and throttling. At the lowest level, various ICs on the board (e.g. power regulators) will turn themselves off if they overheat. Somewhere above that, firmware will definitely exert /some/ control, to cover odd situations like the machine hanging while booting. Above that, the kernel or userspace can add another layer — but like each of the layers before, that layer can only lower the limits further.
Having thermal management in userland (and nowhere else) would be legal suicide. Imagine the lawsuits from people accidentally burning their legs...
I believe you are correct, although I did think that kernel_task was there to help cool the components down, and not simply as a devide to report throttled CPU usage consistently with unthrottled.
That said, I didn't mean to say that thermal throttling only happened in userland but rather that it did happen there, even though it might also happen elsewhere.
Within the context of this thread, this is relevant since in this case the CPU was not being thermally throttled as it was running cool, but something was still throttling the amount of power going to it.
I was merely suggesting that Nextgrid's affirmation that it must have been the firmware throttling the CPU is not necessarily true. Given that there is a software component to thermal management (or at least I thought so), it's only logical to assume that there may be a software component of whatever other throttling was occurring without it necessarily being suicidal as suggested.