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Root New ROMs and Battery Calibration

tobyjuggler

Well-Known Member
Jan 17, 2011
183
40
Firstly, a big thanks to the posters and mods on this forum. I managed to root my phone and apply CM7.1 without having to ask any questions on here and was able to do it simply by reading all the advice given here, especially by El Presidente and D-U-R-X. You guys have the patience of saints! However, now that I have caught the bug, I do have a few questions about battery calibration and applying ROMs.

Firstly, just to be sure I'm right on this, using the apps CurrentWidget and Battery Calibration, is it correct that a full calibration after a ROM installation requires one full charge until the phone is drawing 0mAh from the charger, then a wiping of the stats via Battery Calibration, followed by a full discharge until the phone switches itself off? Is this enough or should this be followed by another full charge from zero to 100% to ensure the full battery capacity range has been captured? What happens if you switch the phone off or carry out a reboot before the first full discharge, do you have to start again?

Secondly, if you want to try a new ROM, when you backup your current ROM, I assume the backup includes the battery stats, so that if you return to your backup there is no need to recalibrate the battery? If this is the case, then I assume that you should finish the calibration cycle before trying a new ROM, due to the battery stats change that will have taken place in the meantime (or start again after restoring a backup)? Obviously, if you stick with your new ROM a fresh calibration is required.

Finally, what exactly is the Dalvik cache? From what I've read and been told it is separate to any backups and should be wiped after any new ROM or return to a backup ROM, is this correct? Does the Dalvik cache contain any of the battery information and therefore going back to backed up ROM means that a fresh battery calibration is required, since you will have wiped the cache?

I love my DHD, it's the best phone I've ever had, but I hate that it can't even do 24 hrs without a fresh charge, except if you just keep it in your pocket and only make and receive the occasional phone call. As soon as you use something like GPS for an hour or so, the battery plughole opens gapingly wide.

So, as one of my main reasons for rooting and applying new ROMs is to improve battery life, like for many other people, but also seeing what new ROMs look like, these are important questions to me. I love the way you can simply return to a previous ROM so easily after trying a new one, but if doing so keeps messing with the battery stats, then it should be avoided, as I don't want to be tied down for several hours just to ensdure that the battery stats are correct. Or am I worrying needlessly?
 
Firstly, a big thanks to the posters and mods on this forum. I managed to root my phone and apply CM7.1 without having to ask any questions on here and was able to do it simply by reading all the advice given here, especially by El Presidente and D-U-R-X. You guys have the patience of saints! However, now that I have caught the bug, I do have a few questions about battery calibration and applying ROMs.

Thanks! :)

Firstly, just to be sure I'm right on this, using the apps CurrentWidget and Battery Calibration, is it correct that a full calibration after a ROM installation requires one full charge until the phone is drawing 0mAh from the charger, then a wiping of the stats via Battery Calibration, followed by a full discharge until the phone switches itself off? Is this enough or should this be followed by another full charge from zero to 100% to ensure the full battery capacity range has been captured? What happens if you switch the phone off or carry out a reboot before the first full discharge, do you have to start again?

That's the right procedure for calibration. It's not essential by any means, but I'd recommend getting into the habbit of doing it. Not sure about the switching off thing, what I'd recommend doing during the discharge if it switches off is letting it die, then if you notice battery life being a bit iffy, calibrate again.

Secondly, if you want to try a new ROM, when you backup your current ROM, I assume the backup includes the battery stats, so that if you return to your backup there is no need to recalibrate the battery? If this is the case, then I assume that you should finish the calibration cycle before trying a new ROM, due to the battery stats change that will have taken place in the meantime (or start again after restoring a backup)? Obviously, if you stick with your new ROM a fresh calibration is required.

Yeah, you'll need to calibrate the battery after a backup. Again, not required, but recommended if you notice performance isn't what it was.

Finally, what exactly is the Dalvik cache? From what I've read and been told it is separate to any backups and should be wiped after any new ROM or return to a backup ROM, is this correct? Does the Dalvik cache contain any of the battery information and therefore going back to backed up ROM means that a fresh battery calibration is required, since you will have wiped the cache?

Are you familiar with what the prefetch data in Windows is? Think of Dalvik cache like that. Dalvik is the java base of what your apks need/use to run. Basically, it's where Android sticks recently and commonly used data so you/it can access it faster.

I love my DHD, it's the best phone I've ever had, but I hate that it can't even do 24 hrs without a fresh charge, except if you just keep it in your pocket and only make and receive the occasional phone call. As soon as you use something like GPS for an hour or so, the battery plughole opens gapingly wide.

So, as one of my main reasons for rooting and applying new ROMs is to improve battery life, like for many other people, but also seeing what new ROMs look like, these are important questions to me. I love the way you can simply return to a previous ROM so easily after trying a new one, but if doing so keeps messing with the battery stats, then it should be avoided, as I don't want to be tied down for several hours just to ensdure that the battery stats are correct. Or am I worrying needlessly?

You're kind of worrying needlessly. I'll always calibrate after a fresh install/restore, but others don't and never have any issues. If you're looking at battery life, did you check out the LorDmod kernel and the Undervolt stuff?
 
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Are you familiar with what the prefetch data in Windows is? Think of Dalvik cache like that. Dalvik is the java base of what your apks need/use to run. Basically, it's where Android sticks recently and commonly used data so you/it can access it faster.
Ah, thanks, so it doesn't matter how often it is wiped it will be rebuilt.

You're kind of worrying needlessly. I'll always calibrate after a fresh install/restore, but others don't and never have any issues. If you're looking at battery life, did you check out the LorDmod kernel and the Undervolt stuff?
Yeah, following your advice in the sticky, I'm using LordMod 8.5 CFS. I've only just started looking at undervolting and am currently using SMARTASSv2 230/1075. I've had a couple of lockups, but these have been on first reboot after a total battery drain. I'm not sure if it's related or not though. I may try going down one more step on the max voltage though to see if I can squeeze a little more life out of the battery.

Thanks for your help.
 
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Ah, thanks, so it doesn't matter how often it is wiped it will be rebuilt.


Yeah, following your advice in the sticky, I'm using LordMod 8.5 CFS. I've only just started looking at undervolting and am currently using SMARTASSv2 230/1075. I've had a couple of lockups, but these have been on first reboot after a total battery drain. I'm not sure if it's related or not though. I may try going down one more step on the max voltage though to see if I can squeeze a little more life out of the battery.

Thanks for your help.

Not at all, it's recommended before a ROM flash as some ROMs don't wipe that area and it can cause issues.

The smartass min/max stuff, that's not voltage btw, that's CPU speed, there's a separate undervolt app you flash in recovery. Did you do that?
 
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Not at all, it's recommended before a ROM flash as some ROMs don't wipe that area and it can cause issues.

The smartass min/max stuff, that's not voltage btw, that's CPU speed, there's a separate undervolt app you flash in recovery. Did you do that?
Oooh, I didn't spot that. Any recommendations? And where are the settings for it, is it a separate app from the CM7 settings?
 
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http://androidforums.com/desire-hd-...as-anybody-rooted-using-tool.html#post3287692

Instructions are in that post, have a read and let me know if there's anything you're not sure about. Lowest to most UV goes as follows: -25, -50, Ultra UV, Stable Pinky, Pinky. Most I can get is -50, but that does me fine. Each phone handles it differently though and I think that J-E-R-K-S D-U-R-X guy has managed Stable Pinky.
 
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Yep, just download the zip, put it on the SD Card, boot into recovery (use ROM Manager to check you have the latest version of CWM installed, 5.0.2.0), don't wipe anything, select install zip from SD Card, wait for the install to complete (it takes seconds), then reboot.

You'll have an app appear in your app drawer called LorDmod UV, the icon is an aliens head, then just use that to select your level of UV. Start off small and work your way up.

Looking at your previous posts though, was the locking a total handset freeze requiring a battery pull or a just a force close with an error message?

Also, have you ran fix permissions in ROM Manager/CWM? If not, try that now.
 
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Looking at your previous posts though, was the locking a total handset freeze requiring a battery pull or a just a force close with an error message?
Yeah, it was a full freeze with screen on and I had to remove the battery. It's only happened twice and on both occasions it was shortly after a reboot following a full battery drain, with the charger plugged in. When I restarted again after re-inserting the battery and plugging in the charger again, all was ok. However, there may be something in the fact that it has repeated itself under exactly the same conditions. If it happens again I'll reset the CPU back to its previous settings, as I don't remember it happening on the original CM7 settings.

Also, have you ran fix permissions in ROM Manager/CWM? If not, try that now.
Yeah, have done this, but no harm doing it again.

Yep, just download the zip, put it on the SD Card, boot into recovery (use ROM Manager to check you have the latest version of CWM installed, 5.0.2.0), don't wipe anything, select install zip from SD Card, wait for the install to complete (it takes seconds), then reboot.

You'll have an app appear in your app drawer called LorDmod UV, the icon is an aliens head, then just use that to select your level of UV. Start off small and work your way up.
Thanks, will try it after checking to see if I get the same locking issue as above or not when I next turn on the phone after a full discharge.
 
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Firstly, a big thanks to the posters and mods on this forum. I managed to root my phone and apply CM7.1 without having to ask any questions on here and was able to do it simply by reading all the advice given here, especially by El Presidente and D-U-R-X. You guys have the patience of saints! However, now that I have caught the bug, I do have a few questions about battery calibration and applying ROMs.

No problem... it's what we're here for!! ;)

Won't go in to answering all questions, as I see my trusty sidekick has already got in there and done the leg work! :rolleyes:

http://androidforums.com/desire-hd-...as-anybody-rooted-using-tool.html#post3287692

Instructions are in that post, have a read and let me know if there's anything you're not sure about. Lowest to most UV goes as follows: -25, -50, Ultra UV, Stable Pinky, Pinky. Most I can get is -50, but that does me fine. Each phone handles it differently though and I think that J-E-R-K-S D-U-R-X guy has managed Stable Pinky.

Yes... this is correct - I have managed Stable Pinky (tried Pinky, but it froze on me, so I just thought that I'd leave it as was (on SP).

For info Toby, I used to get 12 hrs(ish) when I was on stock (although it was getting some pretty heavy use). With the modded kernel and the UV scripts, I get anywhere between 24 and 48 hours and, although I don't hammer my phone as much as when it was new, I don't go easy on it either.
 
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No problem... it's what we're here for!! ;)

Won't go in to answering all questions, as I see my trusty sidekick has already got in there and done the leg work! :rolleyes:



Yes... this is correct - I have managed Stable Pinky (tried Pinky, but it froze on me, so I just thought that I'd leave it as was (on SP).

For info Toby, I used to get 12 hrs(ish) when I was on stock (although it was getting some pretty heavy use). With the modded kernel and the UV scripts, I get anywhere between 24 and 48 hours and, although I don't hammer my phone as much as when it was new, I don't go easy on it either.
I've found that when at home I get decent battery performance with WiFi on permanently and APN data off (24-36 hrs). It's only when I'm out and about that the battery performance gets iffy (12-24 hrs).

Oxygen is a very good ROM, it is seriously bare, probably the most basic ROM that you can get (which is what I tend to like)

I would definitely recommend a try at some point
As I don't use many of the stock apps anyway, I'll definitely be giving this a go.
 
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