iOS 9's impressive 'Low Power Mode' usage gains are not the work of magic, but processor throttling

iOS 9's impressive 'Low Power Mode' usage gains are not the work of magic, but processor throttling
Apple's iOS 9 will drop a bevy of improvements when it hits the scene later on this year, and battery preservation is atop the list of tweaks in store. Cupertino has made some bold claims, too – iOS 9's 'Low Power Mode' can apparently dredge an additional three hours of battery life out of your iPhone or iPad. We already know that the OS will turn off power-hungry features like sensors and push notifications in order to spare those precious droplets of juice. But according to benchmark tests on beta versions of iOS 9, the secret weapon in Low Power Mode's armory is a spot of good, old-fashioned processor throttling.

HTC has engaged in this pastime with its flagship One M9 recently, albeit for different reasons. The Android-powered handset packs Qualcomm's Snapdragon 810, and in order to stop the controversial chipset from overheating, the Taiwanese firm has been forced to reduce performance. Thus, the terms "processor throttling" has gotten a bit of a bad rep over the last few months. 

In the case of iOS 9's Low Power Mode, however, it shouldn't be considered as such. Per the findings of MacRumors running iOS 9 beta through Geekbench 3 for iOS, an iPhone 6 Plus' multi-core score fell from 2,891 to 1,751 with Low Power Mode in action, while single-core performance decreased from 1,606 to 1,019. Proportionally similar conclusions were apparently drawn from an iPhone 5s put through the same test. 

iPhone 6 Plus on iOS 9 beta in normal mode (left) and Low Power Mode

Losing performance is never a desirable trade-off, but when you've only a small portion of battery, all of the cores, RAM, and other high-spec stuff seems less significant. By hindering the processor to the point where presumably, an iPhone or iPad will still manage light and moderate tasks with aplomb, users seeking longevity will be able to bask in hours of additional usage time. 

While the statistics do show clear throttling, it's worth remembering that the software is still in the initial stages of its beta stretch. Thus, things can and surely will change between now and when iOS 9 is ready for prime time, probably around September. 




1. AnTuTu

Posts: 1620; Member since: Oct 14, 2012

Not an Apple fan but I believe processing will be throttled on any device if it is in power saving mode.

5. Finalflash

Posts: 4063; Member since: Jul 23, 2013

Not immediately, only when they reach very low levels of battery. Usually they get by with reducing other services and brightness. Still, lets see if this gets them any more battery life than they had. Seems as though they are trying to find more and more excuses not to increase the battery size and save costs. This will come at the cost of their "buttery" smooth animations which might cost them their image in the long run.

13. Tizo101

Posts: 567; Member since: Jun 05, 2015

what image? iPhones lag so does every phone no need to be embarrassed about it.

14. magnanimus

Posts: 565; Member since: Mar 29, 2013

But it's generally percieved the iPhone lags less than the other phones. They wouldn't wanna break that image.

8. Canaan

Posts: 351; Member since: May 25, 2014

On the Sony Xperia Z3 if you use stamina mode it merely shuts off the apps when the screen is off (though you can control which apps you would like to keep active).

16. Simona unregistered

''Apple delayed innovation'' has Failed :D

19. alaw.14

Posts: 426; Member since: Sep 10, 2013

Your right I did test like this with my note 4 and 3. In idle on my note 4, even with power saving mode on or off, none of the the cores reached pass 1.2 ghz. Doing task with power saving on, the maximum speed the krait 450 cores was 1.9 ghz. When turn off it goes to the maximum 2.7 ghz. On note 3 with power saving on, the max was 1.5 ghz and turned off was 2.3 ghz

23. hound.master

Posts: 1044; Member since: Feb 27, 2015

Nope not WP no performance issues even when it's on and playing.

27. darkkjedii

Posts: 31313; Member since: Feb 05, 2011

We know you're not an Apple fan. Trust me, we know that.

37. Carlitos

Posts: 673; Member since: Oct 23, 2011

Yea I know for a fact that when power saving mode is turned on my Galaxy s4, not only are background processes turned off, but it also limits the maximum performance of the CPU. Same thing with the S5 and S6

2. rick_mobile

Posts: 359; Member since: Dec 13, 2010

Finally, welcome to 2012! :p

4. willytbk

Posts: 252; Member since: Aug 15, 2012

haters yo ! hatersss...

22. Macready

Posts: 1824; Member since: Dec 08, 2014

Can't speak for other phones but my S2 already did this in 2011, when activating power saving mode.

28. darkkjedii

Posts: 31313; Member since: Feb 05, 2011

You should shelf that S2, and upgrade.

3. waddup121 unregistered

Apple doin noob moves. Still haven't caught up to the recent year ahahah

29. darkkjedii

Posts: 31313; Member since: Feb 05, 2011


6. medtxa

Posts: 1655; Member since: Jun 02, 2014

possibly because it's only two cores? thats why more cores are for power efficiency and you don't need to throttled down the cpu for that.

7. nodes

Posts: 1160; Member since: Mar 06, 2014

People's nowadays logic. Low Power Mode == Better Battery != Low Performance. Do you expect a decrease in energy consumption without a performance cost?

36. MrElectrifyer

Posts: 3960; Member since: Oct 21, 2014

Better Battery != Low Performance. That's right, and it's already being achieved with Quad Core and 64-Bit processors. They compute a lot faster, using the same energy, thus you can get more done without penalizing the battery life.

38. nodes

Posts: 1160; Member since: Mar 06, 2014

as far as things go. more cores mean more energy consumption, or is it Android that consumes more power?

9. sssm23 unregistered

do u know Steve Jobs uses blackberry

10. NinjaBanana

Posts: 37; Member since: Apr 20, 2014


15. AlikMalix unregistered

Did you know blackberry is going to end up like Steve Jobs if they dont do something different soon.. (sorry BB fans, this guy been posting this all over - I dont mean for BB to die, quite the opposite) just wanna shut this guy up... Also sssm23, when you go to 3rd grade, they will teach you the difference of past tense and present tense and their magical use in sentences...

17. Simona unregistered

in coffin ?

18. meanestgenius

Posts: 22280; Member since: May 28, 2014

Steve Jobs is dead, you !Diot. He can't "use" anything.

21. AmirBudi

Posts: 88; Member since: Mar 21, 2014

11. Iodine

Posts: 1495; Member since: Jun 19, 2014

Power efficiency improvements to bring up another hour with no features compronised and another three if you don't mind some speed. What's strange on that ? I am actually really excited !

12. iusshpandeh

Posts: 250; Member since: Jul 23, 2014

One day in near future, iPhones will come with long charging cables and millions of reasons to stay near to power socket just because they wont improve battery life!

24. Jimrod

Posts: 1605; Member since: Sep 22, 2014

Strange you say that, my friend bought a Samsung S6 Edge a few weeks ago and is having terrible battery life, having to charge halfway through the day under moderate use - as does another friend with a HTC M8. Apparently it's an issue with Android... We always banter about phones but at a year old my iPhone 6 generally ends the day around 50% and they've conceded that the latest Android OS sucks at the moment for them. Randomly repeated stereotypes don't seem very accurate at present.

25. SamsungEU

Posts: 147; Member since: Dec 29, 2014

Maybe it's a defective unit, my s6 is at aroud 50-60% at the end of the day with moderate usage

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