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A comment on 16-inch MBP 2x slower than M1 MacBook Air in a real-world Rust compile. Parent comment

Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by wmf on Tuesday November 17, 2020 @01:42PM (#25127775)
I’m guessing the performance improvements derive from integrating the memory onto the same chip

Nope, LPDDR4x-4266 is LPDDR4x-4266. Apple, Intel, and AMD all have access to the same RAM. The Firestorm core is the real advantage.

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Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by unixfg on Tuesday November 17, 2020 @11:38PM (#25133267)
A single core being able to fully saturate LPDDR4X bandwidth seems pretty advantageous.

https://www.anandtech.com/show/16252/mac-mini-apple-m1-teste...

“One aspect we’ve never really had the opportunity to test is exactly how good Apple’s cores are in terms of memory bandwidth. Inside of the M1, the results are ground-breaking: A single Firestorm achieves memory reads up to around 58GB/s, with memory writes coming in at 33-36GB/s. Most importantly, memory copies land in at 60 to 62GB/s depending if you’re using scalar or vector instructions. The fact that a single Firestorm core can almost saturate the memory controllers is astounding and something we’ve never seen in a design before.”

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Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by Symmetry on Tuesday November 17, 2020 @04:16PM (#25129967)
You do get a power benefit from keeping the RAM in-socket rather than having to go out over more wires to reach the RAM.
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Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by rbanffy on Tuesday November 17, 2020 @04:21PM (#25130015)
Isn't it attached via a wider bus?
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Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by imtringued on Wednesday November 18, 2020 @03:14AM (#25134283)
The memory bandwidth you get on the M1 is around what you would expect from a dual channel desktop with good RAM. So basically twice as fast as competing laptops.
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Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by wmf on Wednesday November 18, 2020 @12:34PM (#25139653)
Laptops have the same or faster RAM than desktops now.
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Re:16-inch MBP 2x slower than M1 MacBook Air in a real-world... by throwaway894345 on Tuesday November 17, 2020 @02:12PM (#25128236)
Ah, well I'm happy to be mistaken.
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