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A comment on Google developing own CPUs for Chromebook laptops. Parent comment

Re:Google developing own CPUs for Chromebook laptops by Someone on Saturday October 02, 2021 @06:07PM (#28732537)
Nitpick: relative speed differences do not add up; they multiply. A speed of 70 is 40% faster than a speed of 50, and a speed of 100 is 42.8571…% faster than a speed of 70 (corrected from 50. Thanks, mkl!). Conversely, a speed of 70 is 30% slower than a speed of 100, and a speed of 50 is 28.57142…% slower than one of 70.

=> when comparing speed, 70% is about exactly halfway between 50% and 100% (the midpoint being 100%/√2 ≈ 70.7%)

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Re:Google developing own CPUs for Chromebook laptops by zamadatix on Sunday October 03, 2021 @12:03PM (#28738178)
Not sure what the nit is supposed to be, 70% is indeed less than sqrt(1/2) hence me mentioning it. And yes, it's closer to 3/4 than half or full, but the thing being pointed out wasn't "what's the closest fraction" rather "it's really not that close to 1:1".
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Re:Google developing own CPUs for Chromebook laptops by mkl on Saturday October 02, 2021 @06:32PM (#28732701)
> a speed of 100 is 42.8571…% faster than a speed of 50

I think you mean either "100% faster" or "faster than a speed of 70" there.

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Re:Google developing own CPUs for Chromebook laptops by ant6n on Saturday October 02, 2021 @08:27PM (#28733438)
Meh, in the context of emulation, which ran at 5% before JITs, 70% is pretty close to 1:1 performance. Given the M1 is also a faster cpu than any x86 Macbooks, and it´s really a wash (yes, recompiling under arm is faster...)
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