Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

coldjeanzzz

macrumors 6502a
Original poster
Nov 4, 2012
655
17
Sorry if this thread has been done to death, but I'm too lazy to search

My 2012 MBA is getting really bad battery life and I don't know why. It's only like 9 months old. I can just be web browsing and my estimated battery life with drain to less than 4 hours within like 30 minutes of unplugging it (half brightness). When I open up Battery Health it will tell me my current usage and it will be substantially lower than "Web Browsing" even though that's all I'm doing. I mean I have some apps open like Mail or Twitter in the background but they aren't even active. Activity Monitor shows nothing with high CPU usage either

I remember watching the video a while back where they showed "App Nap" or something like that? How much does it actually help?
 
I can just be web browsing and my estimated battery life with drain to less than 4 hours within like 30 minutes of unplugging it (half brightness).
What is the real battery life you are getting? Why do you care what an estimate says? The estimate will change constantly depending on what you have been doing now and in the past. No energy algorithm can predict what you will be doing with your Mac minutes from that point.

In theory, Mavrix should help if you always have multiple apps running but spend a lot of time in only one or two of those at a stretch. Personally, I haven't seen it. Though better, Safari7 is still the king swine of resource hogs.
 
In theory, Mavrix should help if you always have multiple apps running but spend a lot of time in only one or two of those at a stretch. Personally, I haven't seen it. Though better, Safari is still the king swine of resource hogs.

Safari is less of a "resource hog" than Chrome or Firefox though, right?
 
batterylifechart1.jpg
 
I installed the developer preview of Mavericks today and ran my MacBook battery down and noticed about an 1:00-1:15(hour) positive difference over Mountain Lion.

So far I've been happy with OS X Mavericks.
 
A bit off topic but does screen resolution negativly effect battery life? Retina vs MBA?
 

Which laptop / macbook model are those results for? rMBP? 13''/15''??

Thanks

----------

A bit off topic but does screen resolution negativly effect battery life? Retina vs MBA?

The more pixels your laptop has, the more energy it takes to properly light them.

A macbook air running at 1440x900 will consume less energy than a rMBP scaled at 1440x900, simply because the rMBP has way more pixels that need lighting verses the Air.
 
The more pixels your laptop has, the more energy it takes to properly light them.

A macbook air running at 1440x900 will consume less energy than a rMBP scaled at 1440x900, simply because the rMBP has way more pixels that need lighting verses the Air.

And indirectly, you will generally use more power by way of gfx chip to drive them.
 
Now that the GM is out, I am curious about battery life also. My mid-2010 MBP had the best battery life on Snow Leopard 10.6.8. Lion & Mtn. Lion have both brought it down. I usually wait for 10.x.3 update to update, give it time to fix bugs, apps catch up, but (read below), if it's an improvement over Mtn. Lion, and better battery life, I may go for it right away.

Also 10.8.4 & 10.8.5 have both had some issues with memory management. If I do a "purge" at the terminal, things clear up. But, I can be just on Safari, no video and my fan spins up, gets very warm. Quit Safari, and it's still spun up. Sometimes I find my RAM is still in full use, with no apps open..."purge" and it's fixed.

Or, I'll be playing Netflix, never gets HD. Quit Safari, "purge", maybe also use Disk Utiltiy to repair permissions (since putting iTunes 11.1 on), then go back to running Netflix, just a few minutes, it's got HD picture.

WTH? ...Is this fixed in Mavericks?
 
My mid-2010 MBP had the best battery life on Snow Leopard 10.6.8.
I use both 10.9 and 10.6 on an Early 2011. Snow Leopard still beats 10.9 battery-wise using equivalent apps but it's pretty close the best I can tell.

App nap in 10.9 may give it an edge but in reality, you have to be using apps that use a lot of power to begin with and then be in a position for them to "nap". I'm pretty much a one-app-at-a-time guy so it has little effect for me.

And measuring battery life is always subjective from user to user it seems. We'll have to wait for one of the tech blogs to put Mavrix through its paces when it's released.
 
I'm not sure what kind of problems I am experiencing, but my battery life used to be like 7-8 hours (Macbook Pro 13 inch mid 2010) on Mountain Lion. Now it's like 3-4 hours.
 
Just installed the GM. I have a 2010 13" MBP. Went from about 4 hours to 7. That's estimated, though. Considering my battery is poor in health--around 800 of 1000 cycles--that's pretty good.
 
Which laptop / macbook model are those results for? rMBP? 13''/15''??

Thanks

----------



The more pixels your laptop has, the more energy it takes to properly light them.

A macbook air running at 1440x900 will consume less energy than a rMBP scaled at 1440x900, simply because the rMBP has way more pixels that need lighting verses the Air.

This is, for LCD screens, nonsense. The backlight is independent from the amount of pixels: they are LEDs (or in older laptop, CCFL fluorescent tubes) that send light through the pixel raster. There are other technologies where this does matter, but LCD is not one of them.


The higher resolution does however require beefier hardware for the same performance, so for that you will likely indeed see some extra energy usage.
 
No, denser displays really do need a bit more power, they need a brighter backlight as they are less transmissive.

Anyway, Mavericks improves battery life substantially, you will definitely notice a difference. I get an extra hour on my 2011 Macbook Air
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.