Sep 1 2013, 07:25 PM
QUOTE(cowithgun @ Sep 1 2013, 07:16 PM)
if you charge your phone on daily basis, even stock kernel and rom should be good enough.
quad core technically consume more, so starting with NVidia Tegra 3 (first quad core CPU for mobile), kernel already implement auto_hotplug which allow kernel to decide to use only more core when needed.
qualcomm's S4 pro implement it slightly differently using mpdecision - a userland process that something similar. however, since it's not open source, many custom developers decided to removed that and implement the hotplug.
so, even in stock kernel and ROM, it's not that bad.
all stock ROM are using OnDemand CPU governor. in term of power saving this CPU governor is second only to Powersave and sometimes Conservative. most custom ROM using Interactive which may make the phone more responsible, but cannot match the power saving of OnDemand. (On side note, Interactive CPU Governor may not be best for Nexus 4 or any Jellybean android since Project Butter is more effective than CPU governor. it will automatically boost CPU freq on touch.)
there are other settings such as larger data buffering, low memory killer settings, io scheduler, etc that custom ROM may implement to conserve power, but in my testing, they are soooo minor. so custom ROM offer little in power saving nowadays.
custom kernel offers more nowadays. with custom kernel, you can do under-volting. typically allow your CPU to run at same speed (or higher) at lower voltage. other than that, you also can implement lower lowest brightness etc.
although i m still using Stock ROM (with some customization), i m using a custom kernel for power saving and lower heat. ohh... ya, custom kernel allow me to calibrate Nexus 4 screen too, which LG and Google really do not do justice for the IPS screen.
God, you really know a lot. Thanks for the info. Might need your help with what to do with the phone later. What's stopping me is my brother asked me to wait for nexus 5. The price is going to be more expensive right and i can't wait until October (and we don't know when it'll arrive in msia). My xperia u is killing me.quad core technically consume more, so starting with NVidia Tegra 3 (first quad core CPU for mobile), kernel already implement auto_hotplug which allow kernel to decide to use only more core when needed.
qualcomm's S4 pro implement it slightly differently using mpdecision - a userland process that something similar. however, since it's not open source, many custom developers decided to removed that and implement the hotplug.
so, even in stock kernel and ROM, it's not that bad.
all stock ROM are using OnDemand CPU governor. in term of power saving this CPU governor is second only to Powersave and sometimes Conservative. most custom ROM using Interactive which may make the phone more responsible, but cannot match the power saving of OnDemand. (On side note, Interactive CPU Governor may not be best for Nexus 4 or any Jellybean android since Project Butter is more effective than CPU governor. it will automatically boost CPU freq on touch.)
there are other settings such as larger data buffering, low memory killer settings, io scheduler, etc that custom ROM may implement to conserve power, but in my testing, they are soooo minor. so custom ROM offer little in power saving nowadays.
custom kernel offers more nowadays. with custom kernel, you can do under-volting. typically allow your CPU to run at same speed (or higher) at lower voltage. other than that, you also can implement lower lowest brightness etc.
although i m still using Stock ROM (with some customization), i m using a custom kernel for power saving and lower heat. ohh... ya, custom kernel allow me to calibrate Nexus 4 screen too, which LG and Google really do not do justice for the IPS screen.
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