zlacker

>>speckx+(OP)
This used to happen to my MacBook Pro, although it was a non Apple Silicon one. The issue was that I had changed the DHCP lease time on my router from the default to a really low value. I believe I had set it to 15 minutes. What I believe was happening was the MBP was waking up to renew its IP address every 15 minutes and by the time it went to sleep again, it was probably waking back up to repeat the process. Changing the value on the router back to its default completely fixed the battery drain issue on my MacBook Pro. I'd never have guessed the cause-effect except I made the change around the same time I purchased that new MacBook Pro and was paying more attention to any issues that might arise.

>>paulja+hb
That is so weird. How much mAh can a single “wake and renew lease” possibly take? Like it has to be milliamp-milliseconds (mAmS?). I mean my phone is chattering with the cell network probably all the time even in a fairly deep sleep mode. The laptop is lighting up the WiFi stack to send and receive (and process) like a few packets?

Like you said though, it’s pre Apple silicon so who really knows! Maybe it decided to do some other stuff while it was awake?

>>cruffl+mf
Your cell phone modem is completely decoupled from the main processor and is a complete, independent system in itself, so it's optimized to do that.

Bluetooth and WiFi radios on Macs are also semi-independent. They can keep connections alive while the system is in deep sleep.

Waking a big processor, frequency scaling it and turning it off is surprisingly complicated. We disabled SpeedStep in our clusters since frequency scaling visibly affected performance of the systems due to overhead incurred by frequency change. Same is true for waking / sleeping big silicon.

It's complicated, it's wasteful.

Some of the Intel's biggest improvements as their micro-architecture evolved were reduction of the frequency scaling overhead and its performance impact, but this never made the news back in the day because its effect was invisible in consumer class systems even in its most primitive form.

> Maybe it decided to do some other stuff while it was awake?

That's called Power Nap and is enabled only if your computer is connected to power, by default.