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ARM MacBook vs. Intel MacBook

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Re: ARM MacBook vs. Intel MacBook

#81

Post by TinkersW »

rayiner wrote: post #72
TinkersW wrote: post #51

Earlier quoted context omitted.

The article is phrased confusingly, at one point saying there are 4 pipelines, and then saying it can do 4 FADDs and 4 FMULs(for a total of 8) per cycle. So are there 4 or 8?? I believe what they meant to say was 4 FADDs OR 4 FMULs. Then they say it has quadruple the throughput of Intel and older AMD chips, but that doesn't follow unless this does 8 floating point operations per cycle not 4. The image of the pipeline…

Each is a multiply-accumulate instruction: https://developer.arm.com/documentation/dui0473/latest/neon-...

They probably are FMA ports, but they didn't say that anywhere in the article, and it still doesn't explain the "quadruple the throughput", as both of Intels ports are FMA and 2/4 of AMDs are FMA.

Re: ARM MacBook vs. Intel MacBook

#82

Post by ben-schaaf »

userbinator wrote: post #76
nielsbot wrote: post #69

Earlier quoted context omitted.

How does this square with their relatively low power consumption? (Honestly asking--I don't know about this stuff)

I suspect that's largely due to the smaller process size.

To add to this: TSMC states either 15% performance or 30% efficiency gains on 5nm (relative to 7nm). Applying the 30% efficiency gains to the similarly performing Zen 3 CPUs gets you to similar consumption as the M1 (in a load scenario, big little has idle advantages).

Re: ARM MacBook vs. Intel MacBook

#83

Post by secondcoming »

theonemind wrote: post #9

Considering the positive reception of the M1, I'd like to see the cases where the M1 does sorely lose to the Intel chip as the post alludes to. The SIMD sounds promising in that regard, but I don't know processor technology that well. Does anyone know where the Intel chip greatly outdoes the M1?

Heat?

Re: ARM MacBook vs. Intel MacBook

#84

Post by jeffbee »

bacon_blood wrote: post #80
jeffbee wrote: post #55

Earlier quoted context omitted.

These are my personal observations. You can reproduce, but you'll need to bootstrap the Go toolchain first. For example, in your GOROOT: go test -test.bench=Cond2 --test.run=ZZ --test.cpu=1,2,4 sync For me: goos: linux goarch: amd64 pkg: sync BenchmarkCond2 3575089 336 ns/op BenchmarkCond2-2 3236198 370 ns/op BenchmarkCond2-4 2831134 420 ns/op goos: darwin goarch: arm64 pkg: sync BenchmarkCond2 5903233 190.4 ns/op Be…

Go f1980efb92c011eab71aa61b68ccf58d845d1de7 on a Mini on 11.0.1 goos: darwin goarch: arm64 pkg: sync BenchmarkCond2 4849542 249.7 ns/op BenchmarkCond2-2 2639139 531.1 ns/op BenchmarkCond2-4 3112030 393.1 ns/op

Interesting, I can confirm. I wonder if this was the fix.

https://github.com/golang/go/commit/c15593197453b8bf90fc3a90...

Re: ARM MacBook vs. Intel MacBook

#85

Post by hmsync »

Just run the author's benchmark program on my i5-9600k:

    |          | i5-9600k     | i7-7700HQ | Apple M1  |  
    |strtod    | 217.97 MB/s  | 80 MB/s   | 115 MB/s  |  
    |abseil    | 613.48 MB/s  | 460 MB/s  | 580 MB/s  |  
    |fastfloat | 1400.15 MB/s | 1000 MB/s | 1800 MB/s |

Re: ARM MacBook vs. Intel MacBook

#86

Post by fooker »

userbinator wrote: post #23
alwillis wrote: post #5

The M1 has 8 instruction decoders while every Intel processor maxes out at 4. This enables many more instructions in flight than on Intel. The M1 can process twice as many instructions per clock cycle than an x86 processor can.

An x86 instruction can decode into many more uops than an ARM instruction. It could be more accurate to say the M1 can process twice as many half as complex instructions as x86.

Most instructions are simple.

Re: ARM MacBook vs. Intel MacBook

#87

Post by GeekyBear »

ben-schaaf wrote: post #82
userbinator wrote: post #76

Earlier quoted context omitted.

I suspect that's largely due to the smaller process size.

To add to this: TSMC states either 15% performance or 30% efficiency gains on 5nm (relative to 7nm). Applying the 30% efficiency gains to the similarly performing Zen 3 CPUs gets you to similar consumption as the M1 (in a load scenario, big little has idle advantages).

The theory when the first Apple 5nm chip was announced is that Apple took the power efficiency gain.

>The one explanation and theory I have is that Apple might have finally pulled back on their excessive peak power draw at the maximum performance states of the CPUs and GPUs, and thus peak performance wouldn’t have seen such a large jump this generation, but favour more sustainable thermal figures.

Apple’s A12 and A13 chips were large performance upgrades both on the side of the CPU and GPU, however one criticism I had made of the company’s designs is that they both increased the power draw beyond what was usually sustainable in a mobile thermal envelope. This meant that while the designs had amazing peak performance figures, the chips were unable to sustain them for prolonged periods beyond 2-3 minutes. Keeping that in mind, the devices throttled to performance levels that were still ahead of the competition, leaving Apple in a leadership position in terms of efficiency.

https://www.anandtech.com/show/16088/apple-announces-5nm-a14...

Re: ARM MacBook vs. Intel MacBook

#88

Post by aYsY4dDQ2NrcNzA »

cknoxrun wrote: post #48
jaredtn wrote: post #36

Earlier quoted context omitted.

Do all technical advances make you feel sad? Why hang out on Hacker News then?

It's actually a legitimate phenomenon: https://news.ycombinator.com/item?id=15643663

Blinn’s Law

“As technology advances, the rendering time remains constant.”

https://www.fxguide.com/fxfeatured/founders-series-industry-...

Re: ARM MacBook vs. Intel MacBook

#89

Post by kilburn »

arvinsim wrote: post #54
agloeregrets wrote: post #17

What I found shocking is just how drastically faster some workflows are. If you work in JS and Node (say doing unit tests for an angular web app) this machine is so much better it’s unbelievable. It’s probably less than half the time to run tests. Half. It’s real productivity change.

As a JS developer, still waiting for full Homebrew. But then again, I might as well wait for the next iteration of Apple Silicon if that is the case.

Or you can try MacPorts which already supports ARM ;)

https://www.macports.org/

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