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There's No Such Thing As a General-Purpose Processor
CowboyRobot writes: David Chisnall of the University of Cambridge argues that despite the current trend of categorizing processors and accelerators as "general purpose," there really is no such thing and believing in such a device is harmful.
"The problem of dark silicon (the portion of a chip that must be left unpowered) means that it is going to be increasingly viable to have lots of different cores on the same die, as long as most of them are not constantly powered. Efficient designs in such a world will require admitting that there is no one-size-fits-all processor design and that there is a large spectrum, with different trade-offs at different points."
"The problem of dark silicon (the portion of a chip that must be left unpowered) means that it is going to be increasingly viable to have lots of different cores on the same die, as long as most of them are not constantly powered. Efficient designs in such a world will require admitting that there is no one-size-fits-all processor design and that there is a large spectrum, with different trade-offs at different points."
100 watts corresponds to 2000 Calories per day
Also, watt represents momentary consumption and calories are a fixed mass of energy
Calories and calories per day are not the same unit. A calorie is 4.18 kJ, and a calorie per day is 4.18 kJ / 86.4 ks = 48.4 mW. Multiply this by 2000 and you'll end up very close to 100 W.
From TFA:
It's therefore not enough for a processor to be Turing complete in order to be classified as general purpose; it must be able to run all programs efficiently. [emphasis added]
Um, nope.
A general-purpose anything is rarely as efficient at a given task as a special-purpose version of the same thing. Sometimes you really do want your computer chip to be a "Jack of all trades, master of none."
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Sounds like a hottie