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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 l
by ggreer 8y ago
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.
- manmal 8y agoHaving a MacBook Pro Late 2016, I can only dream of 4h battery life with the workload you describe. It has a bigger screen though.
- villedepommes 8y agoMy 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.
- dep_b 8y agoChrome 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.
- saagarjha 8y ago> 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…
- dep_b 8y agoObjective-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.
- squeaky-clean 8y agoDid 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.
- NeedMoreTea 8y agoYes. 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.
- ggreer 8y agoYes. 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_specifications_3 https://en.wikipedia.org/wiki/MacBook_Pro#Technical_specific... and https://en.wikipedia.org/wiki/MacBook_Pro#Technical_specifications_4 https://en.wikipedia.org/wiki/MacBook_Pro#Technical_specific...
- ttsda 8y agoTry 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.
- saagarjha 8y agoYup, 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.
- eitland 8y ago> 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 :-/
- emiliosic 8y agoMy 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
- jjeaff 8y agoThey 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?
- manigandham 8y agoYes. 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.
- admax88q 8y agoThey have too many engineers to make a small efficient program.
- bb01100100 8y agoComment made my day :-)
- SteveNuts 8y agoTheir 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.
- rayiner 8y agoAt 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.
- nicoburns 8y ago> 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.
- mbrumlow 8y agoI 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".
- weavie 8y agoI'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?
- mbrumlow 8y agoCurrently 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.
- weavie 8y agoI 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.
- swiley 8y agoIf 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.
- CoolGuySteve 8y agoWhat 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.
- ggreer 8y agoPowertop 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.
- dgzl 8y agoLong 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.
- killjoywashere 8y ago> 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.
- dgzl 8y agoIs 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.
- k_sze 8y agoThere’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.
- jodrellblank 8y agoSomebody 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).
- tuukkah 8y agoThat'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_display https://en.m.wikipedia.org/wiki/Transflective_liquid-crystal...
- asciimo 8y agoI got the joke about Slack. Loved it.
- saagarjha 8y agoFWIW, 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" ;)
- computerex 8y agoI was wondering if the comment about slack was a jab. Nicely done!