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A comment on M1 iPad Pro over 50% Faster Than Previous Generation in Early Benchmarks. Parent comment

Re:M1 iPad Pro over 50% Faster Than Previous Generation in E... by dmitrygr on Tuesday May 11, 2021 @06:53PM (#27124634)
"50% faster in the same thermal and power envelope" has always been impressive. When CPUs were gaining 100% per year, they were often growing their power use just as fast, if not faster.
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Re:M1 iPad Pro over 50% Faster Than Previous Generation in E... by durst on Tuesday May 11, 2021 @08:19PM (#27125239)
I don't think this is entirely true. (Although please let me know if I misunderstood your comment or if I'm wrong.) While it is true that CPUs' power usage increased significantly between the 1980s and 2006, I believe you were able to get much better performance "in the same thermal and power envelope" during that time period. There's two conflicting factors that made these energy efficiency gains less apparent in the market: power efficiency and power usage. Roughly until 2006, both Dennard Scaling and Moore's Law held, so you got ~2x performance efficiency (performance per watt/performance in the same thermal and power envelope) every 1.5 years. [1,2] Power consumption also increased at the same time [3], so you got both more performance in the same thermal and power envelope (useful for mobile/embedded chips) and greater power consumption (useful for desktop/server chips).

1. https://en.wikipedia.org/wiki/Dennard_scaling#Relation_with_...

2. https://iscaconf.org/isca2018/docs/HennessyPattersonTuringLe... - slide 25

3. http://www.edwardbosworth.com/My5155_Slides/Chapter01/ThePow... - "Here is a Clue to the Problem" graph

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