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Root FYI for those switching from a2sd roms to non a2sd roms.

jreed2560

Android Expert
Dec 31, 2009
3,922
439
Tennessee
Just a little heads up out there for people like me who flash roms ten times a day. If you haven't already experienced this issue, you are likely to come across it in the future.

It is probably a good idea to make a backup of the contents of your sd card to keep when flashing from an a2sd enable rom to a non a2sd enabled rom. If your partitioned for a2sd and flash a non a2sd rom it will hold you phone at the boot screen or send you into an endless boot cycle.

I had to take everything off my sd card, re format the card, then flash the rom before I could load everthing back onto the card.

I may be a total noob, and for all you smart people this is probably a no brainer. But if I can keep anyone else from having this headache I thought it best to post it.
 
no, all you need to do is wipe your partition and things will go back just fine

to wipe the partitions boot to recovery, choose wipe, and choose the option for the sd ext.

dont know the EXACT way its labeled. but its obvious once you get there which one i am talking about.

any issues just feel free to contact me.
 
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So if we switch to a non a2sd rom and we need to wipe our sd partition does that mean we lose the apps that are loaded on the sd card? If that's the case do we then need to go thru the process of downloading our apps again if we flash to an a2sd enabled rom?

Sent from my HERO200 using Tapatalk
 
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Hey question :-/ Sooo I had Evil Eris with OC and A2SD, but now switched to Aloysius v11 with OC & A2SD because it seems to run faster for me... (Evil Eris kept lagging on my phone for some reason).

I did adb shell ls -l /data and it does show that A2SD is working right now... BUTTTT when I attempt to install the apps, they keep Force Closing until I uninstall and reinstall, thennn they seem to work.

It also only shows that I have like 70mb free even tho the apps are installed to the SD and not internal. I'm just confused on what I might be doing wrong. When I had Evil Eris, I had about 130mb free. Thanks to everyone who's been so helpful on here.

By the way, I already tried a wipe of the ext partition.
 
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That sucks. So if youre a flash-a-holic like myself it would just be a pain in the ass to set up a2sd if I will basically have to wipe/download my apps like normal. I really see little benefit to this feature if you dont download a bunch of apps and think you will be flashing different roms often.

Sent from my Aloysius Eris using Tapatalk
 
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Hey question :-/ Sooo I had Evil Eris with OC and A2SD, but now switched to Aloysius v11 with OC & A2SD because it seems to run faster for me... (Evil Eris kept lagging on my phone for some reason).

I did adb shell ls -l /data and it does show that A2SD is working right now... BUTTTT when I attempt to install the apps, they keep Force Closing until I uninstall and reinstall, thennn they seem to work.

It also only shows that I have like 70mb free even tho the apps are installed to the SD and not internal. I'm just confused on what I might be doing wrong. When I had Evil Eris, I had about 130mb free. Thanks to everyone who's been so helpful on here.

By the way, I already tried a wipe of the ext partition.

aloysuis may be running an outdated version, im taking a break from the ROM work for a few days, but shoot me an email with a download link to the rom you are using and when i get back i will take a look at it
kenkyger@gmail.com
 
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That sucks. So if youre a flash-a-holic like myself it would just be a pain in the ass to set up a2sd if I will basically have to wipe/download my apps like normal. I really see little benefit to this feature if you dont download a bunch of apps and think you will be flashing different roms often.

Sent from my Aloysius Eris using Tapatalk


just make sure that whatever roms you are using are a2sd enabled. its not hard to set it up, shouldnt take a dev too long to get it working, if not then just shoot me a message and i can try to get it working for you too.
 
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just make sure that whatever roms you are using are a2sd enabled. its not hard to set it up, shouldnt take a dev too long to get it working, if not then just shoot me a message and i can try to get it working for you too.

Yeah it doesnt seem too hard to set up, but say if a Dev isnt interested in enabling it on their rom from the start, you cant exactly flash to that rom right away to check it out without having to wipe your partition and lose your apps. For myself it literally only takes me about 5 minutes to download and install all 10 or so of my apps before I move on to setting up the rest or my tweaks, so app2sd isnt a big deal for myself and am fine with sticking to the regular way of doing things. Now overclocking tho has turned out to be something that I have seen to work very well so far...
 
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Yeah it doesnt seem too hard to set up, but say if a Dev isnt interested in enabling it on their rom from the start, you cant exactly flash to that rom right away to check it out without having to wipe your partition and lose your apps. For myself it literally only takes me about 5 minutes to download and install all 10 or so of my apps before I move on to setting up the rest or my tweaks, so app2sd isnt a big deal for myself and am fine with sticking to the regular way of doing things. Now overclocking tho has turned out to be something that I have seen to work very well so far...


actually, thorugh some of my tests i have done, using a non a2sd rom doesnt hold your phone at the boot screen, only a rom IMPROPERLY running a2sd does that, what you must have run into is using a rom thats calling up ether an old version of a2sd or one thats calling it up improperly.
 
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i am actually using an Epic 4g, but was wondering about kernels..... i have my rom set up with a2sd, and i'm wondering if i can flash just a different kernel over it? or does a kernel have to be set up for a2sd as well?

Probably it would be better to ask that question in the Epic forums, but here goes anyway: you would probably only run into trouble if the new kernel in question was not compiled with support for "extN" (N=2,3 or 4) filesystems. (Most phones only use fat32 or yaffs2 filesytems).

If you have a way to completely back up / restore the phone (sorry I am not familiar with the Epic) - such as a" Nandroid" backup - then the best answer that can be given is this:

Back up your phone and give it a try. If it doesn't work, just restore the backup.

eu1

[ Edit ] It occurs to me that the above advice is only safe for people who know how to get into their custom recovery and operate it correctly from there - people that only use ROM Manager/ClockworkMod should not experiment this way, as they will be befuddled if their regular OS gets wedged.
 
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Probably it would be better to ask that question in the Epic forums, but here goes anyway: you would probably only run into trouble if the new kernel in question was not compiled with support for "extN" (N=2,3 or 4) filesystems. (Most phones only use fat32 or yaffs2 filesytems).

If you have a way to completely back up / restore the phone (sorry I am not familiar with the Epic) - such as a" Nandroid" backup - then the best answer that can be given is this:

Back up your phone and give it a try. If it doesn't work, just restore the backup.

eu1

[ Edit ] It occurs to me that the above advice is only safe for people who know how to get into their custom recovery and operate it correctly from there - people that only use ROM Manager/ClockworkMod should not experiment this way, as they will be befuddled if their regular OS gets wedged.

hey thanks for the advice... i figured i would ask, since i googled my question, and you guys were on the topic.

the one kernel i flashed on top of my a2sd setup did not work.... the bootup went further than it sometimes does, but did not go all the way. but yeah, I restored my nandroid backup with no problem. thx

edit: actually, i don't think i had to restore my backup..... just reflashed the original kernel back over :)
 
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EU1, if it's a 2.2 ROM that stores apps in the regular fat32 partition and doesn't use the Ext partition, would the extN requirement still hold true?

No, it would not. I assumed that yogi was talking about 2.1 ROMs, but wasn't entirely sure


hey thanks for the advice... i figured i would ask, since i googled my question, and you guys were on the topic.

the one kernel i flashed on top of my a2sd setup did not work.... the bootup went further than it sometimes does, but did not go all the way. but yeah, I restored my nandroid backup with no problem. thx

edit: actually, i don't think i had to restore my backup..... just reflashed the original kernel back over :)


Whether or not the kernel-builder decides to add in extN support probably varies rather widely - for normal Linux builds, it is almost always included in the kernel, since ext2/3/4 are the "default" filesystem types employed for laptop and desktop systems. But for Android it is completely optional - unless the SD card is partitioned and has an ext2/3/4 file system in one of the partitions.

Most of the a2sd/apps2sd implementations rely on boot-time initialization (things like making sure that symlinks are in place, or causing mounts to occur prior to the Android layer starting up) - those things (typically) live inside the boot image - or at least rely on "hooks" in the /init*rc scripts to call other scripts in places like /system/etc or /system/opt. So, if the installer you use only replaces the kernel and repackages the boot image, all of that "extra" stuff should survive. If you replace the complete boot partition, though, all bets are off.

My personal opinion is that a2sd/app2sd or even Froyo external SD storage for apps should never be used unless it becomes absolutely necessary, as it merely adds complications for a ROM-hopper, and provides little benefit (unless you are truly out of space on the phone).

eu1
 
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No, it would not. I assumed that yogi was talking about 2.1 ROMs, but wasn't entirely sure





Whether or not the kernel-builder decides to add in extN support probably varies rather widely - for normal Linux builds, it is almost always included in the kernel, since ext2/3/4 are the "default" filesystem types employed for laptop and desktop systems. But for Android it is completely optional - unless the SD card is partitioned and has an ext2/3/4 file system in one of the partitions.

Most of the a2sd/apps2sd implementations rely on boot-time initialization (things like making sure that symlinks are in place, or causing mounts to occur prior to the Android layer starting up) - those things (typically) live inside the boot image - or at least rely on "hooks" in the /init*rc scripts to call other scripts in places like /system/etc or /system/opt. So, if the installer you use only replaces the kernel and repackages the boot image, all of that "extra" stuff should survive. If you replace the complete boot partition, though, all bets are off.

My personal opinion is that a2sd/app2sd or even Froyo external SD storage for apps should never be used unless it becomes absolutely necessary, as it merely adds complications for a ROM-hopper, and provides little benefit (unless you are truly out of space on the phone).

eu1

ah ok, thx. do you think a2sd also wears down your mem. card, with all the read/writes that are made?

P.S. yep, i'm working with 2.1 roms currently.
 
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ah ok, thx. do you think a2sd also wears down your mem. card, with all the read/writes that are made?

Yes... sort of. It wears it down faster than a yaffs2 filesystem would because ext2/3/4 contains no provisions for wear-leveling, whereas wear leveling is built in to yaffs2. (Note also that read operations cause no wear - only writes).

Practically speaking, though, that is really only a theoretical worry; storing apps on the SD card really doesn't cause all that much writing to occur, compared to the expected number of write/erase cycles for an eraseblock (10,000 to 100,000 write/erase cycles).

Think of it this way: in the FAT32 filesystem that is normally on the SD card, the phone is constantly writing to the same set of memory pages (the FAT tables) as you write or delete files from the card. So - you should expect that over a few (to many) years of service, an SD card will eventually start to develop bad patches whether or not you are using ext in a separate partition - FAT32 is at least as bad as ext2/3, and probably worse.

But that's sort of OK - the SD card is easily replaceable whereas internal memory is not, and you will probably have chucked out your phone and the SD card in favor of a newer version of both before you reach that point.

eu1
 
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