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Comment by ggreer | Hacker News Reader

I don't lie about battery life numbers. People like to say, "I get 9 hours of battery life." when they mean that they get 9 hours if they do doing nothing but let their computer idle with the brightness at minimum. 4 hours with a 55Wh battery is an average consumption of 13 watts. That's because my typical workflow involves running a VM containing cassandra & postrgres (among other services) and recompiling go and javascript. My coworkers with 15" MacBook Pros tend to worry more about battery life than I do.

My fan comment was a joke about Slack's efficiency. Of course compiling a bunch of go code will make the fan turn on. That will use up 100% of your cores on any decent sized project.

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I get about 9 hours of battery life on my T450s and about 6 on my x220 under load, youtube, vms, coding. That is under load.

My idle times, browsing something like HN, or sitting in #emacs I get near 20 hours on my t450s and about 13 on my x220.

I think low low low idle power consumption is key to long infrequent charges. This is because the second you are not using your computer then it should also not be using power. For example, my t450s without adjusting the screen bigness idles at 2.8W, so tons of idle time with a 97WH battery.

You can't really optimize power for when you are using it. If you are compiling, you want the fastest compile time and use the most power. Same for other things that take power.

I go all weekend not charging my personal laptop and the only times I close the lid is when I am going to bed. Otherwise I leave the lid open, same brightness and walk away for hours and come back and continue where I left off.

So I see your point about people saying "I get 9 hours of battery life." doing nothing, but even 9 hours of doing nothing is fairly low, given I can make a 10 year old laptop get close to 18 hours, and a 4 year old one get near 21 hours "doing nothing".

I've just unplugged my x220 and it is telling me it has 4:36 battery remaining. I only have firefox open and not doing anything else, so that 4:36 is probably quite a significant overhead. It will drop as soon as I do something.. Yup, just fired up emacs and now it is saying 3:44 remaining.

Would you mind sharing what setup you have that lets you get such long battery life?

Currently in charge of th baby.

But get power top installed. Make sure in the 4th screen in power top and make sure all settings are to "good". I made a systemd unit to do this for me know boot. I also installed tlp and have it set it's settings. Some of those cross over into what powertop does.

I set some things on the i915 driver but that will have to wait until baby watch is over.

I have just installed powertop and updated the settings. It doesn't seem to have made any difference... but that's probably because I don't know what I am doing. I'll read up on it further. Thanks for the tip.

What battery do you have? The thin one?

Not 100% sure, I'll have to look when I get home this evening. I think it may not be the thin one as it is thicker than the rest of the case, but don't totally know off hand what I should be looking at to determine it..

powertop --auto-tune

Does it for me.

I don’t think it is possible to get the consumption of T450s on X220.

The T450s generation (and the generation before it) use ULV processors (ultra low voltage).

The processors used in the T450s generation have a TLP of 15W.

The processors used in the X220 generation have a TLP of 35W.

On the flip side, the processors in the X220 generation (and in the next generation) are powerful, which is a good thing if you need the power and if you have the laptop plugged most of the time.

The x220 gets about 80% my T450s, it also seems to compile emacs a few seconds faster... Later today I will try and post some screen shots of power consumption. The x220 for sure can last an entire day on battery.

I have horrible battery life on my T520, mainly because the battery is really old.

I wish to purchase a new battery for it and am looking for a place to buy a battery that

1. will ship to Norway without too high shipping cost, and

2. isn’t going to explode in my face.

Any suggestions?

Also, mbrumlow, what distro are you running? And did you customize it in anyway aside from using powertop that you mentioned, to get it to consume low amounts of power while idle?

Track down an OEM Lenovo battery from whatever source you can find. Unfortunately, the aftermarket batteries I've tried all died rapidly, due to cells dying or going out of balance or whatever. Never had an aftermarket last longer than 6 months before it was down to a half hour or something pitiful. Finally sucked it up and bought an OEM battery and two years later it's still giving a couple hours of runtime.

I actually just had the motherboard on my T450s go down. I was regularly getting 10 - 20 hours of development time with the 97WH battery (usually emacs, posgresql, rails and music).

You should be able to optimize and get even higher. I'm actually considering getting a new T480 (since it has the battery expanded slot), but I'm struggling to decide.

What OS are you running? I'm really curious on your setup if you're running Linux. I have the same Thinkpad but it's impossible for me to the the idle wattage like that.

Ubuntu 18.04: https://geoff.greer.fm/images/x210.jpg

That’s what I’m using, not mbrumlow. Also I just upgraded to 18.10 to get a newer kernel and a newer version of the r8169 module. That unlocked PC7 idle states and increased my battery life by 50%.

At my previous job I had a T460p with the full-sized double battery setup, and I routinely got 12 hours actual use with room to spare, and this was on a more or less stock Fedora install without even bothering to do any real power consumption optimizations.

Modern T-series still have amazing damn battery life, and I’ve never found anyone else who comes close except Apple, or Android ARM hybrids like the old ASUS Transformer Prime with the double batteries.

Long lasting battery is the feature I appreciate most from a laptop. My T430 with the extended slice battery gives me 7-10 hours, and could probably get another 3+ if I swapped out the CD drive for the Power Bridge battery.

Long live the ThinkPad.

Edit: This is with mostly casual use on an Arch Linux setup.

I think the next killer feature I want/look for in a laptop is the ability to see the screen in bright sunlight. It's a gorgeous day today and I would mind spending a few hours by the waterfront coding.

> I would mind spending a few hours by the waterfront coding.

I do this with an OLPC XO. I also have a Cr-48 with Lubuntu. There's a tradeoff: the XO has a brighter screen but a smaller keyboard.

Is a brighter screen what we want though? E-ink type screens are excellent in the sun, but lack gorgeous colors... And I'm almost ok with it.

There’s maybe a billion-dollar opportunity there: maybe someone could invent a hybrid screen that switches from (O)LED to e-ink mode under bright lighting conditions.

Somebody did invent a hybrid screen, Pixel Qi, it was used in the Notion Ink Adam tablet from 2010.

But it wasn't a billion-dollar opportunity and Pixel Qi are so forgotten they were reported by the media as closed down, although might technically still exist (and might have released their IP to the public, I haven't read too far on it just now).

That's exactly what OLPC has. And I remember an old Nokia phone having a screen that's both at the same time so that brighter sunlight will just wash out the colors but not the content: https://en.m.wikipedia.org/wiki/Transflective_liquid-crystal...

The OLPC XO with the sunlight readable screen by Pixel Qi is a wonderful machine to use in bright daylight. I love mine.

> Long live the ThinkPad.

This year's models are doing away with replaceable batteries for the most part. T490 has a built-in 50 Whr battery and no ability to extend or replace that without removing screws. It also gets rid of the 2.5 in drive option, one of the RAM slots (but it adds a soldered one), and it replaces the full size SD with a micro-SD. All of that for a small reduction in weight and thickness.

So, basically, the thinkpad line is gone now, it's just another poor macbook pro knockoff. I expect to see articles like this one for years to come, given that there are almost no options left if you want power, expandability and battery life in a single laptop package.

Well if it was a MacBook, everything would be glued-in or soldered, but yes the trend is worrying. I guess the popularity of MacBooks, despite their form-over-function, is what is driving this. But surely they could have kept the T490 like the T480, especially as the T490s exists.

T430 doesn't support Ultrabay battery

At least my 2013 MacBook Pro would get 10 hours of battery life with the screen at medium brightness, WiFi on, and using Safari and Word (which is not a particularly light workload given how heavy the web is these days). Working in Emacs/SBCL would result in even longer battery life. Unless you’re rebuilding Chrome from source every few minutes, the compile-edit cycle is mostly typing into your editor with short bursts of activity in-between. Even more so for languages with lightweight compilers like Go and JS.

> which is not a particularly light workload given how heavy the web is these days

I think a lot of this might be attributable to just how well power-optimised safari is. I could get 10 hours using safari when my macbook was new, but only 6 using chrome or firefox! Given that safari is speed-competitive with these browsers, it's very impressive.

What kind of numbers do you see in powertop between high and low load? (After running powertop --auto-tune and powertop --calibrate of course).

I've noticed the i7-8550U in my HP Envy can easily drive consumption up to 22W during a parallel compile even though I spend most of my time idling between 5 and 7W while editing text. The extra cores seem to consume a lot of power compared to my older 5th-gen laptop with 2 physical cores.

I also wonder if mobile Ryzen behaves similarly or if Intel just trashed their power/thermals in order to compete on core count.

Unfortunately, it's really hard to find benchmarks with power vs load stats. Most of them seem to be like "7 hours watching a movie in Windows" when I'd rather see "Battery is 55 Wh but computer uses 22W when all cores are 100% and 35W at 100% CPU and GPU". You know, like actual facts about the hardware rather than subjective usage experiences.

Powertop doesn't show any wattage numbers for me. I looked at gnome-power-statistics and saw that my laptop idles around 9 watts. That's all power consumption including the screen.

This afternoon I upgraded my kernel from 4.15 to 4.18. Then I removed the r8168 module that I'd tried to use to reduce power consumption. Using the open source r8169 module got me PC7 states. Now my X210 idles at 5 watts. I'm guessing I could go lower if I tweaked more, but this is a huge improvement in battery life. I'm glad I took the time to look into it.

I've gotten battery consumption figures as high as 30 watts when running something like `./minerd --benchmark --threads=8`. Intel claims the i7-8550U has a 15W TDP, but it can easily go above that if it has enough cooling.

> My fan comment was a joke about Slack's efficiency.

It's less of a joke and probably just a statement.

Seriously: even something as small as someone adding an animated emoji makes slack eat CPU :-/

My office decided to move from Jabber (Pidgin / Adium) to Slack. Much of the office upgraded computers. Whether Jabber is negligible, Slack used más two to three Gb RAM. It’s simply the most inefficient software I have to Tun continuously on that PC

They have raised so much money and have so many engineers. Is performance of their app so low priority that no one is working on that?

They have too many engineers to make a small efficient program.

Comment made my day :-)

Their priority was probably shipping a cross-platform app as quickly as possible and gaining adoption. My hunch is they will eventually make native apps for Windows and Mac and drop Linux support.

Dropping Linux support should be getting harder and harder: I've never seen more Linux machines in the office than now.

Yesterday I saw someone here on HN saying they didn't know (something about Windows) because they never used Windows.

Yes. It was first about gaining market share and now it's about integrations to solidify their position against competitors.

Performance is not on the list and probably never will be.

You've answered it yourself:

>They have raised so much money and have so many engineers.

/collapse

I used to wonder why my ThinkPad sometimes ran for 12 hours and sometimes 5. Turns out that Google Docs has an animated cursor that doesn't just blink, it fades in and out using javascript. Animation cost several W on average. UX guys love animations because I dunno they are just psychos.

Reminds me of this: https://news.ycombinator.com/item?id=13940014

(I believe that the 13% CPU nentioned there is a rounded-up 12.5% of the whole CPU, or in other words a full 100% of one of 8 hyperthreads.)

Remarkably similar, yes!

I've always appreciated Windows's animations for minimise and restore. I hate animations that don't do anything for you, though.

Brian Kernighan's COS333 page links to a goodui.org that recommends animations (in moderation) but also a bunch of horrible stuff.

So there's that.

FWIW, I "honestly" get about 7-8 hours out of my MacBook Pro when doing light coding (small C/C++ project builds every five minutes, tweaking my website, writing some shell scripts), and 4-5 when doing "heavy" work such as iOS development. I can eke out 10 or more hours if I only read Mail and Hacker News :P

> My fan comment was a joke about Slack's efficiency.

Hence the "lol" ;)

Having a MacBook Pro Late 2016, I can only dream of 4h battery life with the workload you describe. It has a bigger screen though.

My work laptop is a mbp 2018 (i9, 32GB). The battery life is abysmal. I typically get a little bit over 2 hours. I'm not going to lie though: I'm always running Atom or VSCode and there's lots of opened tabs in Chrome.

Chrome used to half my battery life on a MacBook Pro. On a brand new machine with a full battery I could program all day in Xcode if I forgot my charger until one day it was empty halfway the day. Finally I figured out it was Chrome that killed it so fast.

> On a brand new machine with a full battery I could program all day in Xcode

I'm impressed; with Xcode and the simulator I'm lucky to get anything longer than 6 hours…

Objective-C really is a lot kinder for your battery I guess. Also it was brand new at the time and I guess I was using a phone for debugging.

Did they reduce the battery size on newer models? My 2015 i7 mbp can get about 3 hours of Civ 6 (in strategic view), or 6 hours of regular dev workload. I remember it lasting longer a few years ago too.

Yes. Can't remember how much it shrank in Wh though. I had a 2016 which I ultimately sold after 6 months, then bought a 2015 of eBay. I get roughly 25-33% better battery life on the 2015 than I did with the newer model.

Yes. The previous generation 15" MacBook Pro has a 99.5Wh battery. The 2016 & 2017 15" touchbar MacBook Pro has a 76Wh battery. The 2018 model was upgraded to 83.6Wh. Depending on which version you have, you get either 15% or 25% less battery than the older model.

I got the figures from https://en.wikipedia.org/wiki/MacBook_Pro#Technical_specific... and https://en.wikipedia.org/wiki/MacBook_Pro#Technical_specific...

Try ditching chrome/ff for safari for most of your workload, I find that consistently gives me a few extra hours of battery, and I always have IntelliJ and VScode open and in use.

Yup, switching from Chrome or Firefox to Safari is the number one thing I recommend to people to improve their battery life on Macs. The less Electron they can have as well, the better, but it's slightly less on an issue because it's not running JavaScript trying to sell you ads.

I got the joke about Slack. Loved it.

If you throttle the machine instead of using a fan the battery life only changes by less than half (about 25% in my experience) so machines with bad cooling which I feel like the sort of person who would exaggerate battery life would be more likely to use will actually get better battery life when performing more intense tasks.

I was wondering if the comment about slack was a jab. Nicely done!

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