I started to reply earlier, but I realized I know nothing about Codename's ROM, as I never got around to trying it. So I am not sure of what settings would be in there. I assume they are similar to the kernel settings in most other ROMs (AOKP, CM9, Gummy, BAMF, and many others use a similar setup for their performance settings). But I will give this a shot.
I have been playing around with the setting on CND to TRY to get a better battery life but this is only managing to irritate me because the MOST i get with a "good" battery life is 1 hour extra. Heres what I have currently and please help me understand why (if I am doing something wrong)
When I go to setting> performance> Processor speed>
Minimum - 345MHz
Max - 1190 MHz
CPU - Current: Performance (I can change this to anything I want and STILL no noticeable change in battery life)
Is that your governor that is set to performance? As mentioned I have no clue how CNA is setup, but performance is a governor on some kernels. Performance means it puts your phone into whatever the max is (1190 according to your setup here) and doesn't ever clock down. This could definitely be a battery drainer if I am correct about this.
I have seen this in the the SETTING> PERFORMANCE Menu: processor voltage - i am ASSUMING this is where you set values on how to volt the battery... i played with this but there are 5 settings and nothing that lists what they do so therefor I dont know...I played around with the settings the other day with the phone plugged into the computer. I charged the battery for 3 hours and the MAX I got was 32% as soon as I unplugged it started dropping like a fly. So i did a complete wipe and its back to stock settings.
What 5 settings do you have under processor voltage? I am not very familiar with CNA's ROMs, as it has been a while since I got around to running one.
Im sorry for being 3years to late with asking about undervolting and sorry if I am ranting but im seriously tired of having a full charge when I go to sleep and then wake up with 11% battery life. Or check my work emails for an hour and have to immediately recharge my battery. Everyone keeps saying they get GREAT battery life so why am I the only one who gets screwed?
Undervolting saves a bit of battery (I will get into this in a minute), but it sounds as though you have some other
problems as well. There is no reason why it should drain a massive amount of battery while it is sleeping. I am able to get about 1% per hour drainage at idle. This is on wifi, strong cell signal, with very little syncing. Of course there are so many variables, but ~1% is about as good as I have seen others report without airplane mode.
Things to try/consider :
- The screen is a killer. Turning the brightness down as low as you can stand it is a good idea. At higher brightnesses, the screen will slurp up all of your battery juice quick. Note that tinkering with certain color settings via kernel settings (if available) can darken/lighten the screen. Blacks take less power to display than whites on the Nexus display. There isn't a big difference at the lower brightnesses, but the brighter you get the bigger the difference gets. If you use a specific app/screen a lot, say email or facebook for example. Perhaps a dark themed version can help you salvage an extra few percent by the end of the day.
- If I was right about the performance governor above, trying a less power hungry governor. Interactive or On Demand perhaps? If you don't see either of those, what options do you have? There are also hotplug and hotplugging governors, which allow one of the cores to be disabled when not necessary and/or when screen is off (depending on how the gov is set up). In theory this saves battery (my non-scientific tests have shown rather minimal gains, if any), but some folks have good luck with them (perhaps my device is being stubborn lol).
- Undervolting. This kinda depends on your kernel. Some kernels use Smart Reflex, which does a pretty good job of undervolting on it's own. You can still UV yourself, but it kinda isn't necessary with SR. With kernels that don't have SR, or you just want to take the UV into your own hands. What I do is start with the slowest clock setting I plan on using. I go into my performance settings, set the min and max to that slot, and then lower the voltage on that slot by a little(10mV or so). I run a benchmark and/or stress test (this may take a while on slower speeds), to see if it is stable. If so I go lower. Once I see problems, such as performance problems that weren't apparent at higher voltages, or a soft reboot, I know I have gone too low. I then go to the next slot and repeat this process. Note, never
set at boot unless you are certain the settings are stable.
- Try a different kernel. Different kernels run differently for different devices and ROMs. LeanKernel, Franco, Faux, Popcorn and Glados are probably the most popular. There are other great kernels out there as well that are worth a shot if you would like to try them. Sometimes different kernels will help your device sleep better (which I will get into in a second), sometimes they will have fixes and stuff that provide for better battery life.
- Check if your device is deep sleeping.
https://play.google.com/store/apps/details?id=com.bvalosek.cpuspy <-- that can help see that.
- Check to see if you have wakelocks, and/or what is eating your battery (possible rogue apps). You can look in Settings > Battery and look at what the biggest killers of battery are there.
Better Battery Stats (there is a free version on XDA) or
https://play.google.com/store/apps/details?id=com.gsamlabs.bbm (this is free in market) can help you show if you have wakelocks and what is causing them. Then you can figure out what to do about them. They also do a nice breakdown of each application's usage of battery as well. Find which apps are the problems. Perhaps turn down how often certain things sync if possible.
- Flashing a new ROM. Sometimes new ROMs have fixes that can help with battery (like wakelocks gone that were present in another). Or perhaps a different ROM will just run better on your device.
I am sure there is a lot of things I didn't think of in this post. Sorry for my long post.
