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by fifafu 993 days ago
Just be aware that 1% on modern multi-core systems is not a lot. The macOS activity monitor doesn't calculate the average percentage over all cores, instead (AFAIK) a process on e.g. a M1 Pro/Max can use up to 1000% if it utilizes all 10 cores.

Stuff like this will be run on the efficiency cores, I doubt it will have a lot of impact on anything.

You can see the usage of efficiency vs performance cores by using Activity Monitor => Window => CPU History

2 comments

1% is still a lot for power saving. If the system is idle, it should be at 0%. If it is anything above, then it shows poor design.
Realistically no modern consumer OS is ever at idle for long.

It's constantly monitoring WiFi signals, battery level, checking for background processes to run, and a hundred other things.

Whether CPU usage is being reported as 0% or 1% averaged over the course of a second doesn't have anything to do with poor design. It's just being rounded from values like 0.3% or 0.8% anyways.

Monitoring Wi-Fi signals is, afaik, something that happens on the Wi-Fi chip itself, not the CPU.

While you’re correct that nothing stays truly idle, the modern design is that the main CPU really does stay largely idle because of the power costs involved and instead dedicated microprocessors absorb the load when possible.

Sure, but most modern OSes would inform the user when the WiFi connection dies - so there's something happening on the CPU too.
On a state change, sure. But you're not frequently gaining & losing WiFi access.
The only state where a modern computer is "idle" is when it's turned off.
You can’t really make this claim without measuring the actual impact, especially on a system with frequency scaling and 8+ heterogenous cores.
It's only a fraction of the CPU's power, sure, but it's still consuming power (electricity & processing) without actually doing anything, which is wasteful. And every small inefficiency adds up over the scale of everything.
Perhaps but this thread and discussion might add up to a year's worth of that waste.

Just saying every little thing counts can be very misleading, even though inarguable in theory, and result in non-obvious inefficiency.

> Perhaps but this thread and discussion might add up to a year's worth of that waste.

Don’t forget about the number of macOS users. A lazy search says ~100 million in 2017.

Apple talks a lot about their environmental impact, they spent like 10% of their last event talking about it. So I think it’s fair to criticize them being wasteful here.

in this example it's showing the seconds on the clock, which might be useful to some. (Just pointing out that using < 0.1% of the total CPU (depending on how you'd weight the efficiency cores) should not be a dealbreaker if you like this feature)