[A] Apps2sd and sd-ext partitions explained (to the best of my ability)

[jesusice]

I'm seeing a lot of interest and a lot of confusion here about sd-ext partitions. I hope sharing the little I know will help others.


- By default downloaded apps are installed on the /data partition of your device's internal memory. This is also where the Dalvik cache and the download cache are. Since our Shift's are emmc devices this partition size cannot be changed.

- System apps reside on the /system partition but store their user data (like bookmarks, settings, caches, etc.) on the /data partition. The /system partition size is set and unchangable also.

- The Android OS since 2.2 features native support for apps2sd. This method leaves some of the app still on the /data partition and moves some to a directory it makes on your SD card called .android_secure. Not all apps support this and it is not recommended for alarms, widgets, live wallpapers or launchers due to the way the partitions are mounted during startup. It can increase your app storage capacity but it has it's limits as some of the app data will still reside in /data which is a set size.

- An sd-ext partition is a partition on your SD card that can be used as internal memory. Even though it is on the SD card it cannot be utilized like the SD card. You cannot download files to it and if you check your SD size it will show your card size minus the sd-ext size.

- Unless the ROM supports it or you enable it through a script or mod just having an sd-ext partition on your SD card will do nothing. The OS will not utilize it unless instructed to.

- Scripts like Dark Tremor's or S2E trick Android into thinking that the sd-ext partition is actually part of the /data partition effectively increasing your internal memory. Some scripts will just move the apks onto the sd-ext partition and leave their data on the /data partition and some will keep both the app and it's data on the sd-ext. The script may also allow for moving of the Dalvik cache to sd-ext also.

- Native apps2sd can be used together with the ext partition method. With the sd-ext partition, since the OS thinks that it is part of the internal memory, apps will still give you the option of moving to the SD card. If done it will keep some of the app in sd-ext and move the rest to .android_secure.


And this is my understanding of how apps are stored on Android. If anyone has some insight to share or can correct any incorrect or missing information please do so.

Thanks owed to Joeykrim who once took the time to explain all this to me on IRC. He shares no responsibility for any information I may have misunderstood or was too dumb to grasp

 

[crump84]

Nice write up J-ice.

Sent from my PG06100 using Tapatalk

 

[Erikdrakon]

Ok so i have SSv7.5 with A2sd and my TB and XDA app went to my sd card after updating them and i got the android default icon on the sense screens, if i'm understanding correctly the sytem with A2sd should have just put them on the ext is it possible i did something wrong in formatting my card.

Also my internal storage is still going down more than when i used TB to force apps to sd with native a2sd to get more internal memory, and i have a 16gb sd card and TB tells me i have about 118 user apps.

Should i reformat the card and increase the size, or did i do something wrong in the original setup?

I hope that makes sense of what i'm trying to say

 

[prboy1969]

Ok so i have SSv7.5 with A2sd and my TB and XDA app went to my sd card after updating them and i got the android default icon on the sense screens, if i'm understanding correctly the sytem with A2sd should have just put them on the ext is it possible i did something wrong in formatting my card.

Also my internal storage is still going down more than when i used TB to force apps to sd with native a2sd to get more internal memory, and i have a 16gb sd card and TB tells me i have about 118 user apps.

Should i reformat the card and increase the size, or did i do something wrong in the original setup?

I hope that makes sense of what i'm trying to say

Ok this this has been covered on the SS thread, but here goes. If your internel storage is going down, then the apps are not going where they're supposed to. Also with the Rom having A2SD built in and working there is no need to move anything with TB. When you look at the apps with TB after you fresh install, it will say they're on the internel Mem. But they are not, it's how A2SD works. As far as the Default Android Sense Icon, I've noticed that for some reason certain apps do this. I believe it has something to do with Sense loading faster than the A2SD SD Ext.3 / Ext.4 .

TEAM MiK
Mik Roms Since 3/13/11

 

[Erikdrakon]

yes i get that, they are all on internal but i had moved xda and titanium to internal, and then i noticed i hadn't updated them and when i did they were on native sd which is why they had the stock android icon when i moved them back to internal no problem.

But i am also looking and wondering concerning my space internal 450mb/185mb free and a2sd 1gb/436mb free, and wondering if i did something wrong, or i should increase the size of a2sd

I know a2sd is working just lost me on the updating apps and they went to where they think they are supposed to go rather than a2sd, by that i mean when you go to settings>application>manage applications> sd card none of them should be checked. if i am following correctly.

Plus for example i have tune in radio pro, it does not go to sd but i would force it with TB cause i don't use the widget and it still functioned perfectly on sd can i force those to a2sd as well? to give myself more internal.

I know it's been covered and I've read a lot of post and threads regarding it not trying to drive you guys nuts just want as much info as possible.

 

[prboy1969]

yes i get that, they are all on internal but i had moved xda and titanium to internal, and then i noticed i hadn't updated them and when i did they were on native sd which is why they had the stock android icon when i moved them back to internal no problem.

But i am also looking and wondering concerning my space internal 450mb/185mb free and a2sd 1gb/436mb free, and wondering if i did something wrong, or i should increase the size of a2sd

I know a2sd is working just lost me on the updating apps and they went to where they think they are supposed to go rather than a2sd, by that i mean when you go to settings>application>manage applications> sd card none of them should be checked. if i am following correctly.

Plus for example i have tune in radio pro, it does not go to sd but i would force it with TB cause i don't use the widget and it still functioned perfectly on sd can i force those to a2sd as well? to give myself more internal.

I know it's been covered and I've read a lot of post and threads regarding it not trying to drive you guys nuts just want as much info as possible.

Well no the apps are not on Internel Memory. They are on the SD Ext. that is created with A2SD. The phone only thinks they are on internel. If you have a 1GB partition that is plenty large enough for most people. Also whenever you load an app it is automatically loaded to the SD Ext. You do not have to force move anything.

 

[lionhealth]

I am so new with this subject , so can anyone show me how to trick android with sd card? Is there any other thread introduce more detail the way to do it? thanks

 

[strapped365]

I am so new with this subject , so can anyone show me how to trick android with sd card? Is there any other thread introduce more detail the way to do it? thanks

Have an ext partiton and run a ROM that has a2sd enbaled

Sent from my myTouch_4G_Slide using Tapatalk 2

 

[crump84]

Have an ext partiton and run a ROM that has a2sd enbaled

Sent from my myTouch_4G_Slide using Tapatalk 2

Or if you're running a ROM that doesn't have a2sd built in, use link2sd. Great app, available on the market for free.

Sent from my PG06100 using Tapatalk 2

 

[rugo32]

you lost me at hello

I'm seeing a lot of interest and a lot of confusion here about sd-ext partitions. I hope sharing the little I know will help others.


- By default downloaded apps are installed on the /data partition of your device's internal memory. This is also where the Dalvik cache and the download cache are. Since our Shift's are emmc devices this partition size cannot be changed.

- System apps reside on the /system partition but store their user data (like bookmarks, settings, caches, etc.) on the /data partition. The /system partition size is set and unchangable also.

- The Android OS since 2.2 features native support for apps2sd. This method leaves some of the app still on the /data partition and moves some to a directory it makes on your SD card called .android_secure. Not all apps support this and it is not recommended for alarms, widgets, live wallpapers or launchers due to the way the partitions are mounted during startup. It can increase your app storage capacity but it has it's limits as some of the app data will still reside in /data which is a set size.

- An sd-ext partition is a partition on your SD card that can be used as internal memory. Even though it is on the SD card it cannot be utilized like the SD card. You cannot download files to it and if you check your SD size it will show your card size minus the sd-ext size.

- Unless the ROM supports it or you enable it through a script or mod just having an sd-ext partition on your SD card will do nothing. The OS will not utilize it unless instructed to.

- Scripts like Dark Tremor's or S2E trick Android into thinking that the sd-ext partition is actually part of the /data partition effectively increasing your internal memory. Some scripts will just move the apks onto the sd-ext partition and leave their data on the /data partition and some will keep both the app and it's data on the sd-ext. The script may also allow for moving of the Dalvik cache to sd-ext also.

- Native apps2sd can be used together with the ext partition method. With the sd-ext partition, since the OS thinks that it is part of the internal memory, apps will still give you the option of moving to the SD card. If done it will keep some of the app in sd-ext and move the rest to .android_secure.


And this is my understanding of how apps are stored on Android. If anyone has some insight to share or can correct any incorrect or missing information please do so.

Thanks owed to Joeykrim who once took the time to explain all this to me on IRC. He shares no responsibility for any information I may have misunderstood or was too dumb to grasp

Like Linux..no?

 

[sparksco]

Native apps2ext is the only thing that shows up in Titanium Backup as official apps2sd BTW just thought I would point that out. Not sure why it is that way but it's nice to be able to look in titanium backup and see how full the sd-ext is..

 

[Chad The Pathfinder]

Sparksco, I noticed that your system rom says 351mb free. I checked mine and it says only 26.2mb free. Is that normal?

Sent from my PG06100 using xda premium

 

[YoungCorruptionV2.0]

^^^it depends on the Rom your using. It looks like he is running aosp and your running sense. Aosp is "lighter" than sense is so that's probably why

Sent from my EVO using Tapatalk 2

 

[Chad The Pathfinder]

Yea that's probably it. I'm running MikRunny right now.

Sent from my PG06100 using xda premium

 

[Lord AJ]

I'm seeing a lot of interest and a lot of confusion here about sd-ext partitions. I hope sharing the little I know will help others.


- By default downloaded apps are installed on the /data partition of your device's internal memory. This is also where the Dalvik cache and the download cache are. Since our Shift's are emmc devices this partition size cannot be changed.

- System apps reside on the /system partition but store their user data (like bookmarks, settings, caches, etc.) on the /data partition. The /system partition size is set and unchangable also.

- The Android OS since 2.2 features native support for apps2sd. This method leaves some of the app still on the /data partition and moves some to a directory it makes on your SD card called .android_secure. Not all apps support this and it is not recommended for alarms, widgets, live wallpapers or launchers due to the way the partitions are mounted during startup. It can increase your app storage capacity but it has it's limits as some of the app data will still reside in /data which is a set size.

- An sd-ext partition is a partition on your SD card that can be used as internal memory. Even though it is on the SD card it cannot be utilized like the SD card. You cannot download files to it and if you check your SD size it will show your card size minus the sd-ext size.

- Unless the ROM supports it or you enable it through a script or mod just having an sd-ext partition on your SD card will do nothing. The OS will not utilize it unless instructed to.

- Scripts like Dark Tremor's or S2E trick Android into thinking that the sd-ext partition is actually part of the /data partition effectively increasing your internal memory. Some scripts will just move the apks onto the sd-ext partition and leave their data on the /data partition and some will keep both the app and it's data on the sd-ext. The script may also allow for moving of the Dalvik cache to sd-ext also.

- Native apps2sd can be used together with the ext partition method. With the sd-ext partition, since the OS thinks that it is part of the internal memory, apps will still give you the option of moving to the SD card. If done it will keep some of the app in sd-ext and move the rest to .android_secure.


And this is my understanding of how apps are stored on Android. If anyone has some insight to share or can correct any incorrect or missing information please do so.

Thanks owed to Joeykrim who once took the time to explain all this to me on IRC. He shares no responsibility for any information I may have misunderstood or was too dumb to grasp

That was quite informative. Thanks pal.