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> Once you look closely at power profiles on modern machines you'll see that most energy is going into display and GPU. CPUs mostly run idle. Even if you had a theoretical CPU using zero energy, most people are not going to get 30% battery life gains

This doesn't really seem to match my experience; at least on a 2015 MBP, the CPU is always consuming at least 0.5-1W, even with nothing running. If I open a webpage (or leave a site with a bunch of ads open), the CPU alone can easily start consuming 6-7 watts for a single core.

Apple claims 10 hours of battery life with a 70-something WH battery, which would indicate they expect total average power consumption to be around 7W; even the idle number is a decent percentage of that.

(Also, has anyone been able to measure the actual power consumption of the A-series CPUs?)

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A typical laptop display can consume around 10W all the time so the 1W from the idle CPU is negligible in comparison.

If anything, you should install an adblocker. A single website filled with ads (and they're all filled with tons of ads) can spin the CPU to tens of watts forever, significantly draining the battery.

Anecdotal evidence: On my work notebook (Lenovo X1 Carbon, Windows 10), the fan starts spinning when Slack is on a channel with animated emoji reactions.

My anecdote mirrors yours, plus an extra nod towards animated 'gif' wars.

I'll turn your anecdote into an anecdatum and say the same; for all devices I've owned. (Linux on a Precision 5520 w/ Xeon CPU, Macbook pro 15" 2019 model, Mac Pro 2013)

Turn off animated gifs and emojis in slack.

You can do that? /me looks it up... OMG you can do that. Thank you so much!

That’s because Slack runs on top of basically Chrome, which is a horrible battery hog.

If you run the web versions of Electron “apps” in Safari you’ll get substantially better battery life. (Of course, still not perfect; irrespective of browser all of these types of apps are incredibly poorly optimized from a client-side performance perspective.

If large companies making tools like slack had any respect for their users they would ship a dedicated desktop app, and it would support more OS features while using a small fraction of the computing resources.

(Large-company-sponsored web apps seem to be generally getting worse over time. Gmail for example uses several times more CPU/memory/bandwidth than it used to a few years ago, while simultaneously being much glitchier and laggier.)

Yes, Electron is a bit of a battery hog. But the Slack app itself is horrendous. If you read through their API docs and then try to figure out how to recreate the app, you'll see why. The architecture of the API simply does not match the functionality of the app, so there is constant network communication, constant work being done in the background, etc.

Why does a CPU running 500+ gigaflops struggle to animate a gif? Is the software stack really that bad?

On my laptop, scrolling through Discord's GIF list can cause Chrome and Discord to hard-lock until I kill the GPU process. Possibly because of a bug in AMD's GPU drivers on Windows.

never leave slack in the foreground.

I looked up the numbers out of curiosity. The X1 Carbon has a i7-8650U processor which does about 26 GFlops. The Cray-1, the classic 1976 supercomputer did 130 MFlops. The Cray-1 weighed 5.5 tons, used 115 kW of power, and cost $8 million. The Cray-1 was used for nuclear weapon design, seismic analysis, high-energy physics, weather analysis and so forth. The X1 Carbon is roughly equivalent to 200 Crays and (according to the previous comment) displays animated emojis with some effort. I think there's something wrong with software.

> I think there's something wrong with software.

Amen

Well yes, it's quite noticeably sluggish and bloated on the whole, with even UIs seemingly getting worse over time. Probably doesn't help that everything these days wants to push and pull from multiple networked sources instead of being more self-contained.

10w is on the high end of this, my 1080p screen on my Precision 5520 sucks down a paltry 1.5w at mid brightness, the big killer is the wifi chip. That takes between 1.5-5w.

CPU tends to be quite lean, until something needs to be done then steps up very quickly to consuming 45w.

I usually consider 5 to 15W for laptop display consumption. Depends on the display, size and brightness.

It's quite variable, the highest brightness can consume double of the lowest brightness for example. One interesting test if one has a battery app showing instant consumption (I know lenovo laptops used to do), is to adjust brightness and see the impact.

Yeah, this is probably harder to do on a macbook, but intels 'powertop' program on Linux has quite high fidelity, matches the system discharge rate reported by the kernels battery monitor too.

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