12 ms·
4 W of power is nuts. Less than most LED light bulbs we have in the house.
by NL807 5y ago
4 W of power is nuts. Less than most LED light bulbs we have in the house.
- gigatexal 5y agoImagine a laptop that was just E-Cores but 1.5x the IPC, a la some future M-revision but with defects where they only shipped it with say 8 E-Cores ... that'd be perfect for me and even better if it was in the 12-inch MacBook form factor just with an edge-to-edge screen.
- marcan_42 5y agoAnd the entire M1 SoC uses about 100 mW with the OS ~idle, screen on, writing this HN comment: ANE Power: 0 mW DRAM Power: 32 mW CPU Power: 85 mW GPU Power: 18 mW Package Power: 103 mW I've left an M1 Air powered on, screen off, WiFi connected, SSH session active and running a shell loop printing the date every minute from another machine. After 3 hours, the battery was still at 100%, and the system finally went to sleep and killed the session. Waking it up, after another 3 hours, it had dropped to 98%. That is how you do power management.
- gigatexal 5y agomarcan eh? are you by chance https://twitter.com/marcan42 https://twitter.com/marcan42 ;-)? I can not wait for proper linux -- installable by a noob like me on an m1 -- to be available. Thank you for the 100x time again for your efforts here
- marcan_42 5y agoYes, that's me :-) Easily installable Linux shouldn't take much longer, for those adventurous enough to be happy with a bunch of missing hardware support (but still a usable machine for a subset of use cases). We're pretty much tying up loose ends to get to that point now, I have a quickly shrinking list of TODOs. Of course, "proper" support for everything will take longer :-)
- Aeolos 5y agoIs there something we can do to help, short off diving into reverse engineering?
- marcan_42 5y agoReverse engineering isn't that scary! Seriously though, a big part of my role in the first year has been building tooling to make that part of the process efficient and enjoyable for everyone. We have a Python REPL for interacting with the bare metal hardware, scaffolding for building prototypes of hardware drivers in it (e.g. register and register map definitions), things like the ability to run functions on another CPU core for SMP tests, hardware exception handling so it's actually hard to crash and have to reboot, and even a hypervisor that can run full macOS and inspect all of its hardware accesses, with a rich event tracing framework that goes from raw register maps to coprocessor message passing to decoding remote procedure calls with C++ argument unmarshaling between firmware and the OS, in both directions. All controlled from any host machine running Linux or macOS, over a simple USB connection with the target.
- gigatexal 5y agoHoly smokes! I had no idea, but honestly, that makes a ton of sense. Something that's always fascinated me are drivers -- those lowlevel bits of software make everything so nice. Sucks when something isn't supported. But it's one thing to take a spec and having docs and things to write one but soemthing clearly more amazing to have to reverse engineer something and then write a driver for it.
- jjtheblunt 5y agocan't you install linux on an M1 with Parallels already, which uses user space hypervisor.framework?
- wincy 5y agoAstounding! Whereas I just got a laptop from work, a Dell Inspiron that dies if I leave it in my backpack over the weekend. How has x86-64 managed to go so wrong for mobile devices and power usage? Is it really purely because of backwards compatibility cruft, or just goals that aren’t aligned with low power usage in idle?
- marcan_42 5y agoI think it's a bit of both, plus corporate culture at Intel/AMD not getting it (especially Intel) and then OEMs screwing things up even more with all the hardware around the CPU proper. E.g. I have an x86 laptop where the SSD gets warm in standby; clearly that's not going to do any good for standby battery life. Since Apple controls the whole stack, they can make sure all this stuff is done properly from top to bottom.
- wtallis 5y ago> E.g. I have an x86 laptop where the SSD gets warm in standby NVMe power management is frequently this hilariously bad. There's no real coordination between the NVMe and PCIe specs on power management features, so you can end up with drives that have undeclared dependencies where you aren't supposed to try to use a certain NVMe power state unless you also have a certain level of PCIe link state power management enabled. If you break the drive's assumptions, it'll usually freak out and turn off all power management, leading to power consumption often higher than when the drive's in its active power state but not doing anything. And Microsoft's NVMe driver avoids using a lot of the power management functionality that drives implement, so laptop OEMs and drive vendors have little incentive to clean up the mess (not that they're any good at ensuring the power management techniques used by Windows aren't broken).
- formerly_proven 5y agoThe M1 Air has a ~50 Wh battery, ~2 % over ~six hours is ~0.15 W total system power. For comparison, I'm getting ~0.9 W total system power under similar conditions on a five year old laptop (i5-7200U, 16 GB non-LP DDR4, no memory DVFS, MX500 SATA SSD, 1080p IPS screen). But you'll likely find that the screen/display system is the biggest power hog in light use. For the laptop above just turning the screen on at a low brightness requires around 1.3 W (for a total system power of around 2.2-2.3 W).
- hhh 5y agoHow do you measure consumption with this granularity?