Is anyone using SetCPU with gingerbread?
I'm using GingerVillain 1.5 but I can't seem to find the right profiles with SetCPU.
Oc'd @ 1,2 Ghz without profiles.
Because when I use the screen off profile, my screen sometimes won't turn on.
Screen off - min 245 max 1200
Can someone help me finding the right profiles?
Share your user experience.
In my experience and many others too, the profiles are not needed. The only profile you should ever need is a temperature profile and that's only if you really have it cranked up.
Having a screen off profile is always bad since switching to another profile doesn't happen instantly - there are polling intervals involved and until the next cycle runs your phone will still be using the screen off profile. That makes the phone slow which causes SetCPU to take longer in switching profiles, bogs down the cpu and it becomes a vicious cycle for a few seconds (sometimes a couple minutes). All the while it's draing your battery because the cpu has to work harder. Even regular profiles eat the battery due to the constant querying of the systems status and processing power used for that - which is the main reason you'll hear people whining about their battery life (some aren't effected as much).
Profiles are just not a good idea except for a temp profile for those that oc to the higher GHz (probably 1.4+).
You could try using cpu tuner instead. Gives you way more options.
CM 7
You have a lot of options with cpu tuner.
What triggers and/or profiles do you use?
My screen on/off has been working fine with CM7 nightlies before and after the RC1. I've been using SetCPU with a normal profile of 1017max/245min and a screen off profile of 365max/245min.
I think your issue is with overclocking. Idk about Gingervillain but as far as CM7 goes lots of people are having issues with the on/off animations and wakelock issues when overclocked over 1ghz. Try using your profiles and clocking at or under 1ghz and see how things change.
Not sure why anyone would really need a higher clock than 1ghz but what do I know. I dont see any slowdowns at 1017mhz and I feel that anything faster than that would lead to heat or battery issues?
Yes, screen off profiles work. But they drain your battery faster than if you have no profiles.
Sent from my T-Mobile G2 running Cyanogenmod.
thanks bro, i OC'd to 1017 and there are no issues
ibemad1 said:
Yes, screen off profiles work. But they drain your battery faster than if you have no profiles.
Sent from my T-Mobile G2 running Cyanogenmod.
Click to expand...
Click to collapse
I'm not so sure about this. Have you tested this at all? Starting using screen off profiles of 365max/245min have really increased my battery life, especially when my phone sits idle for a decent amount of time. I don't think you could see more battery life by leaving the clock at 1ghz while the screen is off.
martonikaj said:
I'm not so sure about this. Have you tested this at all? Starting using screen off profiles of 365max/245min have really increased my battery life, especially when my phone sits idle for a decent amount of time. I don't think you could see more battery life by leaving the clock at 1ghz while the screen is off.
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Click to collapse
Every kernel that I know of out there drops down the clock cycle when the screen times out. The reason not having the screen off profile saves the battery is because SetCPU isn't constantly sending requests about the phones state and then checking that against your profiles to see if it meets the parameters set in them.
Now it could be a bit different for you. You might have a different set up or different apps that make having a screen off profile useful (ones that constantly update or run in some way). You just have to watch your phone for a few days and get an app that keeps track of that stuff so you know which route to take.
KCRic said:
Now it could be a bit different for you. You might have a different set up or different apps that make having a screen off profile useful (ones that constantly update or run in some way). You just have to watch your phone for a few days and get an app that keeps track of that stuff so you know which route to take.
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Click to collapse
This is very true. It is definitely hard to make a blanket statement because no two people have the exact same setup. All I was saying is what I've been doin with the screen off animation and I've been having pretty solid battery numbers.
Related
I'm really struggling with battery life at the moment. Has anyone got settings I can use to save on battery life in SetCpu? Profiles etc
+1
I'd like to know too.
I would also like to know =[ my battery dies wayy too fast. I have the darkstone froyo build on my htc hd2 phone energy rom. Any programs or SETcpu settings that will help out?
If your on a rom with preflock disabled then you can underclock.
The only thing you need to change in setcpu really is to make a profile for screen off and set it to 245 (or whatever is the lowest I can't remember) both max and min (leave it on demand, or interactive if your rom has that).
This should give you about 10-15 hours longer battery life
so i wouldnt have to make any other profiles like battery? temperature? stuff like that? should i get rid of my green power and advanced task killer?
No you can keep them (well I don't know what green power is....)
The other profiles are mainly only needed if your OVERCLOCKING, however if your not touching the default max (main profile) then your not overclocking (1ghz).
To save power you UNDERCLOCK which setting a lowered screen off profile would do.
If your slowing the CPU down then the temperature will not rise, so that profile is not needed.
And you don't need to slow the phone down when your using it so none of the others are really needed either.
No you can keep them (well I don't know what green power is....)
The other profiles are mainly only needed if your OVERCLOCKING, however if your not touching the default max (main profile) then your not overclocking (1ghz).
To save power you UNDERCLOCK which setting a lowered screen off profile would do.
If your slowing the CPU down then the temperature will not rise, so that profile is not needed.
And you don't need to slow the phone down when your using it so none of the others are really needed either.
i think im kinda get what you're saying (sorry im kind of slow) so i had just deleted my other profiles and made a screen off one have it set to max all the way right and min all the way left, on demand, priority 100. Now on the main screen i think i touched it cause i read somewhere for max all the way to the right and min all the way to the left. This is confusing lol
The settings I have for my Desire:
Default:
Conservative 245-998
Profiles:
Screen Off - Priority 100 - Powersave
Charging/Full - Priority 50 - OnDemand 245-1305
Battery < 30 - Priority 0 - PowerSave
Running along side JuiceDefender, battery life is acceptable to me
jdeezyboo said:
so i wouldnt have to make any other profiles like battery? temperature? stuff like that? should i get rid of my green power and advanced task killer?
Click to expand...
Click to collapse
Remove everything, setcpu included
Sent from an ipho.../ NETWORK DOWN-PLEASE DON'T TOUCH THE PHONE
Remove everything, setcpu included
Sent from an ipho.../ NETWORK DOWN-PLEASE DON'T TOUCH THE PHONE
__________________
When Chuck Norris holds the Iphone4, the signal increases
That totally defeated the purpose of my question and others before me. Our battery lifes sucked without any programs so now we delete it?
I used darkstones froyo for awhile too. Battery drain killed it for me. I had no luck with anything. Changed to a nand build and its much better. Apparently SD builds just use more battery. With the SD froyo I could never stay below 60ma a few times would drop to less than 10ma but just not consistent. I lost about 8% an hour in sleep mode. Give a well designed nand build a go. In sleep I hover AT 4ma. My battery with Moderate use easily last the day, heavy use (multiple calls, emails, and browsing for an hour or two) still does require a recharge
Im using carbon ara theme with pcb just turn data off wen aint using it via toggle and have a profile for sleep in set cpu for min and max of 245 and from full charfe at 7am by 6 pm im still 65%. Thats using fb checkin email playing angrybirds and checking the forum
Sent from my HTC Desire using XDA App
I also use advanced task killer and kill all tasks wen not in.use
Sent from my HTC Desire using XDA App
bad idea as you are actually making your battery work more by doing that.
Sent from my HTC Desire using XDA App
So I'm on a visionary temp root, overclocked with setcpu. Ive set up several different profiles but I've noticed that my battery life with the profiles isnt as good as other users have claimed.
I have noticed that when i open setcpu sometimes a little message will flash up saying that setcpu has been given superuser permissions. Does this mean that prior to opening the program, it didnt have permissions? If it in fact did not have superuser permissions, could that be why my battery life is less than expected? (i.e. The program didnt have permissions and thus couldnt use the profiles to slow down cpu speed upon screen off, etc.) The message does not come up every time I open setcpu, but it seems to come up when I havent opened the app recently.
Any ideas?
cmccollough said:
So I'm on a visionary temp root, overclocked with setcpu. Ive set up several different profiles but I've noticed that my battery life with the profiles isnt as good as other users have claimed.
I have noticed that when i open setcpu sometimes a little message will flash up saying that setcpu has been given superuser permissions. Does this mean that prior to opening the program, it didnt have permissions? If it in fact did not have superuser permissions, could that be why my battery life is less than expected? (i.e. The program didnt have permissions and thus couldnt use the profiles to slow down cpu speed upon screen off, etc.) The message does not come up every time I open setcpu, but it seems to come up when I havent opened the app recently.
Any ideas?
Click to expand...
Click to collapse
From my understanding, you only set it once. i had set a widget because i thought set cpu had to be running. But i deleted it because if you think about it....superuser app already has the permissions set, and when you open setcpu it shows the current speed.....if it wasnt working it would show 800mhz then KICK into 1 ghz?....thats what i think. You shouldnt need to worry.
Great, thanks for the response.
Sent from my HTC Vision using XDA App
same here. from time to time this popup comes.
anyway i cannot see any benefit from running setcpu as the profiles are not working for me.
i tried setting up screen off profile. this never triggers.
i leave setcpu deinstalled now. battery life is good so far
snudel said:
i tried setting up screen off profile. this never triggers.
Click to expand...
Click to collapse
How can you tell if it triggers or not?
cmccollough said:
How can you tell if it triggers or not?
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Click to collapse
Good question. Can't find anything in logcat.
set notifications.
on the magic you could see him switching profiles right after turning on the screen
you wont see it on the g2
I agree, something is fishy with this. EVERY time I open setcpu it gives me the su permissions granted window like its not being saved in memory
Sent from my HTC Vision using XDA App
EDIT: After shopping around on the market I came across an app called "CPU Tuner". The UI is nice and has roughly the same customization as setcpu if not more. It does take a bit of getting used too but i'm more than willing since the profile notification actually cycles with this app vs. setcpu. I'll give it a shakedown tomorrow as it's getting too late here to test.
cpu tuner doesn't work for me.
in profiles, it just shows 700mhz to 800mhz, which makes it useless as i want to underclock to 200 when screen is off.
That toast pop-up is nothing to worry about, its just something that has featured in the last couple of SU builds, it doesn't mean your app is not working.
I just turn the notification off in the SU settings.
I can now confirm that the screen off profile is not working correctly. Before going to sleep last night, my phone had a charge of 99%. I did not have anything running (no wifi, bluetooth, sync, etc.) and I woke up to 81% battery. It never killed that much overnight before overclocking. We gotta get this fixed.
Sent from my HTC Vision using XDA App
cmccollough said:
I can now confirm that the screen off profile is not working correctly. Before going to sleep last night, my phone had a charge of 99%. I did not have anything running (no wifi, bluetooth, sync, etc.) and I woke up to 81% battery. It never killed that much overnight before overclocking. We gotta get this fixed.
Sent from my HTC Vision using XDA App
Click to expand...
Click to collapse
i have mine set to 1ghz max 245 min profile screen off 245/245 priority--100..and put a widget on my main screen. My phone has been on screen off for the pat 5 hours....and drained only 2% battery life.....i dont understand why it doesnt work with some peoples phones??!!. is it different cause im using a desire z and yours a g2?...i HARDLY doubt that would be a problem :S..
have you tried the widget?.when going to running services, my setcpu app has been running for ever. aka profiles and setcpu working.
jark99 said:
i have mine set to 1ghz max 245 min profile screen off 245/245 priority--100..and put a widget on my main screen. My phone has been on screen off for the pat 5 hours....and drained only 2% battery life.....i dont understand why it doesnt work with some peoples phones??!!. is it different cause im using a desire z and yours a g2?...i HARDLY doubt that would be a problem :S..
have you tried the widget?.when going to running services, my setcpu app has been running for ever. aka profiles and setcpu working.
Click to expand...
Click to collapse
Running the setcpu widget on my phone caused instability issues at higher clocks (feeling ballzy w/ flippy's 1.8 kernel). After removing the widget my profiles were hit and miss for some reason.
As far as the battery issue goes, anyone running CM RC2 and earlier might want to check out nightly 36, apparently there was a memory leak causing battery drainage ( I don't know anything about what it means but common sense leads me to believe a leak is bad lol). If anyone is still not satisfied with setcpu I highly recommend CPU tuner.
jark99 said:
have you tried the widget?.when going to running services, my setcpu app has been running for ever. aka profiles and setcpu working.
Click to expand...
Click to collapse
Yes I have the widget on my homescreen. Weird that so many people get different results
Could the scaling be giving people varying results? I don't even really know what they do, I have mine set on ondemand. Would someone mind sharing what exactly the different scalings do?
cmccollough said:
Could the scaling be giving people varying results? I don't even really know what they do, I have mine set on ondemand. Would someone mind sharing what exactly the different scalings do?
Click to expand...
Click to collapse
http://www.droidforums.net/forum/rescue-squad-guides/47871-overclocking-101-a.html
Centered around the OG Droid but basic concepts still stand.
- Just picked up an app called SuperPower, had it a while back and had issues..but it's been update a lot since then. Looks like it's an all purpose battery management app that has the ability to govern cpu speed also. I'll test drive it and see how it works.
My battery life has improved markedly since installing CM nightly #36 and Pershoot's latest kernel. I've been using my phone pretty heavily over the last 8hours and still have over 50% left. Lots of texts, emails and websurfing etc.
I'm looking to optimize my battery life without sacrificing performance when I need it. I know it sounds easier said than done, but I figure that if anyone might know how, they'd be here. My goal here is to have the performance when I need it, and to keep the battery preserved when I don't.
I'm rooted and running ViperROM 4.0.4 Trinity v2.0. I have the "Genocide 1.2GhzOC EB13 Kernel v0.3a" kernel also flashed to my phone. SetCPU is installed and I've set up my profiles, but I think I may be doing something wrong with them.
I am using autodetect settings as is recommended for adjusting clockspeed. Everything is set to on boot. All profiles are set to conservative as I'm not sure which ones actually apply. Below are screens for everything I have currently set up.
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Am I doing anything wrong here? And if not, is there anything I need to do to improve battery life without sacrificing performance?
I would bump your charging max to 1200Mhz and keep the min at 1000Mhz, although I keep max and min while charging through AC power at 1200Mhz.
Your screen off profile is fine. If you get hiccups or missed calls for any reason, bump the max up to 400Mhz.
If you can run it smoothly, set your minimums for your battery profiles to 100Mhz. It what I'm at now and it runs fine. You may want to keep your minimum for your "screen off" profile at 200Mhz if you get hiccups or missed calls like I mentioned before.
As for your battery <50% profile, I'd set the min at 200Mhz if you're wanting to save battery. Don't want the phone running at a higher clock when it doesn't need it. That's the point of running the min lower.
I personally uncheck the "set on boot" to allow SetCPU to always come back to the appropriate profile rather than going back to the default setting.
Also, set a Battery < 101% profile which will be your new default. I have mine at max 1000Mhz and min 100Mhz and it works well.
Also, conservative simply means the battery will remain at the lowest possible clock until it needs more juice. Assuming it starts at 200Mhz, it'll bump up to 400Mhz, 800Mhz, etc. depending on what the demand is. It will jump frequencies from 200Mhz to 1000Mhz if necessary.
On Demand means the CPU will either be at your minimum set clock frequency or your maximum.
On Demand is usually the most compatible/stable, but the conservative setting is best for battery/performance if your kernel allows it.
Hope this helps =). Let us know if you have more questions.
EDIT: The "set on boot" button simply sets the min and max that's shown on the main screen in SetCPU. If this button is unchecked but the "enable" button on the profiles menu is checked, your profiles will still adjust accordingly.
I can't really see the profiles but do you have the Max set at 400 when the battery is under 50%? If you do your phone will crawl. The 1000 is undervolted. That way you get speed and save battery. And on demand does not.mean that your CPU is either at min. Or Max. It means that it Scales faster then Conservative does. My profiles are when battery is less than 50% I go to 1000/100 and when screen is off I'm at 200/100 all set on demand. My regular setting.is 1200/100.
Sent From My Evo Killer!
I'd like to hijack this since I have a similar question.
I'm using ACS Frozen 1.0 and have the latest SetCPU and am still getting pretty crummy battery life.
The weird thing is that in SetCPU the maximum CPU frequency is always 1.2ghz even if I drag the slider down to 1.0. I don't currently have any profiles enabled that would cause this, so why won't SetCPU let me top off a 1ghz undervolted instead of 1.2ghz?
My battery life definitely hasn't improved at that's a big bummer for me :\
I also have a question. I kept getting a message about superusers rights not being given. I searched to see how to grant SU rights, but could not fond any. I turned the phone off and on, and that message did not pop up anymore.
Now the main screen I cannot adjust any of the numbers, is this normal? I can however enable and make profiles. I made the first one if temp is greater then 0 (I obviously do not want it like this, but its just a test) then it should be OC to 1200. When I saved this in the top right hand corner it says I am at 1200, however when I bring up a program, and go to setcpu and look at the main screen it says 1000.
So what am I doing wrong.
badbeats said:
I also have a question. I kept getting a message about superusers rights not being given. I searched to see how to grant SU rights, but could not fond any. I turned the phone off and on, and that message did not pop up anymore.
Now the main screen I cannot adjust any of the numbers, is this normal? I can however enable and make profiles. I made the first one if temp is greater then 0 (I obviously do not want it like this, but its just a test) then it should be OC to 1200. When I saved this in the top right hand corner it says I am at 1200, however when I bring up a program, and go to setcpu and look at the main screen it says 1000.
So what am I doing wrong.
Click to expand...
Click to collapse
This might be a dumb question, but is your phone fully rooted?
I think so I used Clockwork mod 3.0.6 and I am running Bonsai 3, with 2.2.1
ZeppelinJ0 said:
I'd like to hijack this since I have a similar question.
I'm using ACS Frozen 1.0 and have the latest SetCPU and am still getting pretty crummy battery life.
The weird thing is that in SetCPU the maximum CPU frequency is always 1.2ghz even if I drag the slider down to 1.0. I don't currently have any profiles enabled that would cause this, so why won't SetCPU let me top off a 1ghz undervolted instead of 1.2ghz?
My battery life definitely hasn't improved at that's a big bummer for me :\
Click to expand...
Click to collapse
Yeah I hear you, I get the same crummy battery life with SyndicateROM, I was dying for the 30 hours ! Starting to think it's the battery itself.
musclehead84 said:
I can't really see the profiles but do you have the Max set at 400 when the battery is under 50%? If you do your phone will crawl. The 1000 is undervolted. That way you get speed and save battery. And on demand does not.mean that your CPU is either at min. Or Max. It means that it Scales faster then Conservative does. My profiles are when battery is less than 50% I go to 1000/100 and when screen is off I'm at 200/100 all set on demand. My regular setting.is 1200/100.
Sent From My Evo Killer!
Click to expand...
Click to collapse
Do you keep your 1200/100 on conservative? And what's the battery life you're getting on average? Dummy question but you know...
I'm going to try out this setting today actually with BakedSnack.
Referring to those of you getting "crummy" battery life. The screen takes so much battery many other things don't come into play. Therefore, if you're getting 4-6 hours of screen-on time, you're getting about what everyone else is getting. Those who report 30 hours+ probably have there phone idle more often than not.
Blankrubber said:
Referring to those of you getting "crummy" battery life. The screen takes so much battery many other things don't come into play. Therefore, if you're getting 4-6 hours of screen-on time, you're getting about what everyone else is getting. Those who report 30 hours+ probably have there phone idle more often than not.
Click to expand...
Click to collapse
Ahh this is a good point then. I'm still confused though why when I set my SetCPU to 1ghz it still keeps it at 1.2 :\
ZeppelinJ0 said:
Ahh this is a good point then. I'm still confused though why when I set my SetCPU to 1ghz it still keeps it at 1.2 :\
Click to expand...
Click to collapse
Did you update to the latest Twilight kernel? It's 1.0.1 I believe. Try that as I believed it fixed some CPU scaling issues. Just install the zip in CW, but I'd still wipe cache at last, just in case.
Sent from my SPH-D700 using XDA App
Blankrubber said:
Did you update to the latest Twilight kernel? It's 1.0.1 I believe. Try that as I believed it fixed some CPU scaling issues. Just install the zip in CW, but I'd still wipe cache at last, just in case.
Sent from my SPH-D700 using XDA App
Click to expand...
Click to collapse
+1 I think this was a bug with the original release of Twilight Zone that was fixed in 1.0.1.
Blankrubber said:
Did you update to the latest Twilight kernel? It's 1.0.1 I believe. Try that as I believed it fixed some CPU scaling issues. Just install the zip in CW, but I'd still wipe cache at last, just in case.
Sent from my SPH-D700 using XDA App
Click to expand...
Click to collapse
I'm trying this out right away, thanks!
This whiny message brought to you by the letter E for Epic 4g
i just flashed invisibleks .37 kernal with OMFGB (ran into some problems with CM7) and i was wondering the proper way to set up setcpu profiles with smartass (if needed at all)
Sorry. This should be in Q&A.....
Sent from my OMFGB powered hTc Incredible.
watt9493 said:
i just flashed invisibleks .37 kernal with OMFGB (ran into some problems with CM7) and i was wondering the proper way to set up setcpu profiles with smartass (if needed at all)
Click to expand...
Click to collapse
I ran OMFGB 1.1.1 for a long time before they screwed up 1.2(soooooo many errors), and really felt the need to have a lockscreen music controler(1.1.1 doesn't). I always ran 128/768, on 1.1.1 it should run perfect(I run chad's kernel though), just unlock slowly. If you want a faster unlock set it 245/768. Either one of those will get you really good battery life(128 being better obviously). If you are running 1.2, I highly recommend you set it atleast at 921(i think) or above as that just doesn't run as smooth. Also note the way smartass works, unless you want to kill battery life everytime you turn the screen on, try to set the max the lowest possible as it will sit as a frequency the phone feels it should run at without losing any speed(most of the time it's 1036 if you've overclocked). So unless you are just texting or calling, it's not bad, but any multitasking or big app using when the screen on, it'll jump way up.
I believe Chad is working on an ingenious kernel that tries to scale intelligently to what it is doing at all times so it'll save battery life not only when the screen is off, but also while the screen is on.
Can i set profiles or no? Like screen off, battery ones, and one temp one?
Sent from my OMFGB powered hTc Incredible.
watt9493 said:
Can i set profiles or no? Like screen off, battery ones, and one temp one?
Sent from my OMFGB powered hTc Incredible.
Click to expand...
Click to collapse
Oh, well, there is no point for a screen off one if you are using smartass on all your profiles. When it's not doing anything, it automatically scales down to the lowest setting possible(128 for best battery but slow unlock speeds or double clicks sometimes, 245 fixes those problems but using a fraction more battery).
I have a Normal profile(128/768), a Temp profile(245/614), just make sure if you are using GPS you manually scale it up some, my phone always ran like crap when Navigating anything less then 883, but everything, and I mean everything usually was fine at 768 on 1.1.1. If you are running 1.2 probably want to do 883 then 998 for GPS.
I recently have bought a Defy plus.
Stock 2.3.4 ROM used so far with LauncherPro.
Doing OK with battery life so far, but now starting to look at the CPU over/underclock capabilities. Started with Antutu CPU Master and CPUTuner also.
One thing I haven't seen as yet is the ability to underclock clock below the min 300MHz.. or even whether this makes sense. I guess undervolting is the other option, but perhaps someone can guide me here.
use setvsel to oc/uv, thats the easiest and best app imo. although underclocking your phone below 300mhz may cause instability and makes the phone wake up much slower in my experience.
sent from my cm7 defy...
I agree with zakoo2: Going below 300 will not be a good idea and it will most likely not improve your battery life in any significant way:
My Defy is running between 300-600Mhz and right now the LCD screen is the biggest consumer: Changing the (auto-)brightness settings in CM7 will do *much* more to your battery life than going below 300mhz.
What really helps saving battery life: use setvsel and leave the minimum clockspeed at 300MHz, but set a vsel value of about 20 for it, then scroll down and enable "limit to vsel1 while screen is off".
Also, going below 300MHz will probably make the phone sluggish when waking up from sleep like if a call comes.
Sent from my MB525 using XDA App
im just change from 300mhz to 330mhz lowest. 300mhz will make my defy+ lag when got incoming call. im using smartass govenor.
I heard some guy out there got 80 MHz and running, but I'm not sure of it.
As people said, clocks lower then 300 MHz would make your phone run horribly while waking up (i.e., it would take a long time for the screen to turn on when receiving a call, and you would probably miss it most of the times). Setting 300 as VSel1 and limitting to it while screen is off (2nd-init enabled bootmenu has this option, and downloading SetVSel - free at Android Market - will also do the trick if you have a rooted, but stock ROM) will help you save a lot of juice. Using a lightweight launcher (I personally recommend MetroUI or Zeam) also boosts up batt saving. Last, but not least, setting brightness to auto or minimum (using frosted/mat screen protectors will help a lot while using the phone under direct sunlight) also saves loads of charge.
Obviously, using a light ROM (I think Barebones may be a good option, though I think it's not suitable for me, but it's a personal matter) and calibrating your battery in a monthly basis (via manual calibration - you can find how to do so by googling -, wiping batt stats in custom recovery and/or using the batt calibration app included in most ROMs - but also free at AM) also help.