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

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

#51

Post by alecthomas »

spockz wrote: post #36
oregontechninja wrote: post #33

Earlier quoted context omitted.

I was an unbeliever, but we got some M1 Mac Mini's and this is the result. They even beat the dedicated workstation many of our people have set up. I get when people say it won't quite match a new ryzen for compute power, but in all of our tests, the M1 beat out all our workstations.

What workloads do you run? I’ve got a 16GiB M1 mbp and a 2019 maxed intel and when compiling Java/sbt projects the intel is significantly quicker, albeit also much loader and power hungry.

As the sibling comment mentions, if you're running Intel JDK on M1 it will be slow. You can find M1 native JDK builds here: https://www.azul.com/downloads/?version=java-11-lts&os=macos...

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

#52

Post by pizza234 »

StavrosK wrote: post #45
ahartmetz wrote: post #35

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…

There's an interesting Stack Overflow question/answers: https://askubuntu.com/q/126664.

In general terms, one either just installs the specifically recompiled package (-preempt, -lowlatency etc.), or recompiles their own. The related parameters can't be enabled, because they're chosen as kernel configuration, and compiled in.

I'd take such changes with a big grain of salt, because they're very much subject to perceptive bias.

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

#53

Post by adrianN »

StavrosK wrote: post #45
ahartmetz wrote: post #35

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…

If there were one simple trick to make your computer feel faster without downsides, defaults would change.

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

#54

Post by twoodfin »

I wonder if shunting background processes to the slower efficiency cores has a salutary effect on other elements of system load. I’m thinking of tasks like Time Machine, which presumably are throwing out IOPS at a commensurately lower rate when effectively throttled by the efficiency cores.

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

#55

Post by stefan_ »

bombcar wrote: post #27
jackcviers3 wrote: post #23

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)

It's nice but with additional limitations - on a normal Unix system even if you nice everything to the lowest level possible they'll still take over all cores. This limits things below a certain nice level to the efficiency cores, meaning that the performance cores are always available for foreground action.

Nothing has ever stopped Apple from pinning indexing work to specific cores. They just didn't give a shit.

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

#57

Post by kllrnohj »

coldtea wrote: post #49
theresAt wrote: post #42

Earlier quoted context omitted.

M1 will soon have a fan due to the overheating issue. Although I imagine given how slow the response was on the butterfly keyboard issue it might be a few years out.

What overheating issue? There isn't one in M1.

There isn't any thermal slowdowns on the M1 devices with a fan, no. The only M1 device without a fan shows thermal limitations, though.

Not an overheating issue, no, but the M1 still benefits from a fan, and obviously whatever Apple does in a Mac Pro class machine will also have a fan. They aren't going to keep at ~25W in a full size desktop, that'd be nonsense.

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

#58

Post by chrisseaton »

spockz wrote: post #36
oregontechninja wrote: post #33

Earlier quoted context omitted.

I was an unbeliever, but we got some M1 Mac Mini's and this is the result. They even beat the dedicated workstation many of our people have set up. I get when people say it won't quite match a new ryzen for compute power, but in all of our tests, the M1 beat out all our workstations.

What workloads do you run? I’ve got a 16GiB M1 mbp and a 2019 maxed intel and when compiling Java/sbt projects the intel is significantly quicker, albeit also much loader and power hungry.

> 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.

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

#59

Post by Aaargh20318 »

icedchai wrote: post #38
SigmundA wrote: post #24

Earlier quoted context omitted.

Memory is unified its just not on die. CPU and GPU and AI share unified memory which means zero copy transfers between them.

I laughed when they called it “unified memory.” Amazing what some marketing can do. In previous years, that was called “shared graphics memory” and it was only for low end systems.

Shared graphics-memory is not the same as unified memory.

In a shared graphics-memory system, a part of the system RAM is reserved for the GPU. The amount of RAM reported to the OS is the total RAM minus the chunk reserved the GPU uses. The OS only can use it's own part, and cannot access the GPU memory (and vice versa). If you want to make something available to the GPU, it still has to be copied to the reserved GPU part.

In unified memory both the OS and the GPU can access the entire range of memory, no need for a (slow) copy. Consoles use the same strategy (using fast GDDR for both system and GPU), and it's one of the reasons consoles punch above their weight graphically.

The main reason that high-end GPUs use discrete memory is because they use high-bandwidth memory that has to live very close to the GPU. The user-replaceable RAM modules in a typical PC are much too far away from the GPU to use the same kind of high bandwidth memory. If you drop the 'user replaceable' requirement and place everything close together, you can have the benefits of both high bandwidth and unified memory.

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

#60

Post by SigmundA »

icedchai wrote: post #38
SigmundA wrote: post #24

Earlier quoted context omitted.

Memory is unified its just not on die. CPU and GPU and AI share unified memory which means zero copy transfers between them.

I laughed when they called it “unified memory.” Amazing what some marketing can do. In previous years, that was called “shared graphics memory” and it was only for low end systems.

Its not a new term, copying data between cpu and gpu memory has always been expensive:

https://docs.microsoft.com/en-us/windows/win32/direct3d11/un...

https://patents.justia.com/patent/9373182

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