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How M1 Macs feel faster than Intel models: it’s about QoS

eclecticlight.co

81–90 of 427 posts

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#81

Earlier quoted context omitted.

> when compiling Java/sbt projects Are you comparing a binary being run under dynamic binary translation with a native binary? Not really an honest comparison, if that's the case.

No idea if that's the case, but I wouldn't have expected Java of all things to be run under binary translation.

> I wouldn't have expected Java of all things to be run under binary translation

Depends which version you have installed. It's a taken a while for the native versions to reach the mainstream channels, so unless you've specifically installed an M1 build you probably have an x86 build being run under translation.

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#82

Earlier quoted context omitted.

Try a low latency kernel on your desktop if you use Linux, that should improve responsiveness some more. Apparently the increase in power consumption is minimal - I use (K)Ubuntu's low-latency kernel even on laptops these days.

I run KUbuntu, how can I enable this? EDIT: I searched a bit and, although I haven't found instructions anywhere, I did find people saying that the low-latency kernel decreases throughput as a tradeoff to lower latency. Have you found this to be the case? Also, another source says that the preempt kernel might be better for some workloads: https://itectec.com/ubuntu/ubuntu-choose-a-low-latency-kerne... Can anyone com…

Basically you install linux-lowlatency and reboot. Grub will prefer it over the generic kernel. Make sure that you also get linux-modules-extra in the lowlatency version or you might boot into a system with missing drivers. Happened on my laptop when I switched to lowlatency.

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#83

Launching apps takes ages on M1 mini. Reminded me of the good Windows Phone times.

Strange. With the exception of electron apps (which are slow everywhere), I've found my M1 mini to be extremely responsive. Much moreso than my 16" mpb.

VS Code launches instantly on my i7-4770 under Linux with XFCE. Same under Windows.

So do Slack and Spotify...

That's an 8 year old CPU! If you're having issues, the problem lies elsewhere not with Electron.

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#84

So, like nice[1], except the developer sets the level of importance ahead of time? Makes sense, as long as I can reprioritize if needed. 1. https://en.wikipedia.org/wiki/Nice_(Unix)

Maybe like the big.little cores of many ARM CPU in Android phone?

I'm not familiar with Android APP, maybe there are similar APIs in Android?

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#85

This certainly makes a lot of sense, and it's a brilliant strategy to improve overall performance. But it doesn't account for the full picture either. My M1 Macbook Pro feels about as responsive as my desktop system with an AMD Ryzen 3900X, which is impressive to say the least. It doesn't quite have the raw computing power of the 3900X, but given that it's a portable device that's something else.

Try a low latency kernel on your desktop if you use Linux, that should improve responsiveness some more. Apparently the increase in power consumption is minimal - I use (K)Ubuntu's low-latency kernel even on laptops these days.

I feel it's kind of sad this doesn't happen automatically for distros specially geared to be installed on workstations. You sacrifice a tiny bit of throughput for making the computer continually smooth even under heavy load.

This, automatically turning on battery optimizations when an internal battery is detected, and automatically applying a 'small speaker' EQ to internal speakers are a few changes that would make Linux feel so much better on a laptop.

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#86
post #75

It does not just feel faster, in many cases it is faster. E.g. compiling Rust code is so much faster that it is not even funny. cargo install -f ripgrep takes 22 seconds on a Mac Book Air with M1, same on a hexacore 2020 Dell XPS 17 with 64GB RAM takes 34 seconds.

Hard to compare without mentioning the actual CPU in it. FWIW my Ryzen 3900X completes that compile in 15s.

To be fair, that is a relatively high-end desktop CPU, but it's also a massive margin for a last-gen model.

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#87

What about priority inversion? If a high QoS thread waits on a low QoS one? It seems like it would be a bigger issue here as the low QoS threads are only ever run on half the cores.

Grand Central Dispatch (the OS-level framework that handles these QoS classes) elevates the priority of a queue if there is high priority work waiting on low priority work to finish.

https://developer.apple.com/library/archive/documentation/Pe...

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#89
The other half of the story for the efficiency cores seems to be the battery life. Most of these non-urgent background tasks are put on efficiency cores not only to separate them from my applications, but also to enable this insanely good battery life.

Re: How M1 Macs feel faster than Intel models: it’s about QoS

#90
post #78
post #74

My 16 inch pro Intel is plenty fast - for the first 45 seconds before thermal throttling kicks in. I have a feeling the M1 is faster because it can actually do work for more than just the briefest bursts

Apples intel MBP thermals are pretty abysmal wrt noise. My off brand 7th gen i7 sounds about the same as my colleagues similarly species MBP, but never throttles. There were even people saying they deliberately sabotaged their intel thermals to make the up and coming M1 look better.

Those conspiracy theories were never confirmed. Linus thought the MacBook Air Early 2020 model’s cooling was clearly designed for an M1, but then the M1 launched without a fan at all.
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