Internal SD vs External SD

[DJLittleMike]

It's a noobish question, but I'm still a bit confused as to the internal vs external sd card usage. I know that in some ROMs (currently using SHOstock) the internal 12GB sd is under /mnt/sdcard and the external is under /mnt/sdcard/external_sd, but I never can get anything to use the external card. Why do we have the ability to stick one in our phones if none of our apps can be moved there? The only thing I've been able to use it for is Vignette or things like that where the app configuration allows you to browse to what folder you'd like to use for storage.

What I'm getting at, is that I'd like to move the apps themselves to the external SD, because I have the ability to put a 32GB card in, as opposed to the 12GB internal. Is this possible?

Another related question - TiBu sees my external card's free space, but whenever I use the App2SD function to move it to the "external" card, it moves it to the internal card. Anyone know how to fix this? I'm guessing that it has to do with no ext4 partition on the external SD, but I could be wrong. If that's the case, we're out of luck unless we're running Linux boxes, correct? If that's the case, then I return to my original question - what is the point of having an external SD card if the only thing you can put on it is pictures and/or manually move stuff over using a file explorer app?

 

[Entropy512]

The point is to store large media files like movies.

TiBu will also save to external SD.

Note that some apps use the newer Android standard for internal/sdcard mountpoints (/emmc for internal, /sdcard for external), which Samsung does NOT follow. (CyanogenMod, however, does follow this standard.)

 

[MotoMudder77]

TiBu will also save to external SD.

Thats a negative. TiBu save files are stored in internal.

Main bonus for having external sdcard for me, is the abilitiy to store pictures and videos. Anything that is no on external sdcard will be lost if the phone gets broken.

 

[kingpin32]

They save to internal as default but you can change it to the external SD in the settings options.

Sent from my GT-I9100 using Tapatalk

 

[Stevenrogers_420]

Thats a negative. TiBu save files are stored in internal.

Main bonus for having external sdcard for me, is the abilitiy to store pictures and videos. Anything that is no on external sdcard will be lost if the phone gets broken.

If you noticed he said "will" which means it has the capability. It's in TiBu settings.. You can move them to your external sdcard with TiBu as well...

Sent from my SAMSUNG-SGH-I777 using xda premium

 

[DJLittleMike]

Thats a negative. TiBu save files are stored in internal.

Main bonus for having external sdcard for me, is the abilitiy to store pictures and videos. Anything that is no on external sdcard will be lost if the phone gets broken.

That's not true - you can have TiBu save backups to external storage in the settings menu - you just browse to where you want it to save it.

In either case, so really, just to move movies and other large media over to it? Nothing (aside from the few cases) automatically? Like I can't move apps over to it? It has to be the internal? To me that mostly defeats the purpose of having external storage.

 

[geomax45]

That's not true - you can have TiBu save backups to external storage in the settings menu - you just browse to where you want it to save it.

In either case, so really, just to move movies and other large media over to it? Nothing (aside from the few cases) automatically? Like I can't move apps over to it? It has to be the internal? To me that mostly defeats the purpose of having external storage.

Where do you store your. Nandroid backups? I use the external card for that as well, along with TiBu backups, photos and videos. I sure as hell would not want all of that stuff on the internal storage?

Sent from my GT-I9100 using xda premium

 

[garyd9]

... I'll try to answer the OP question. However, I haven't been around android long enough for this to be an authoritive answer. It's more along the lines of a guess...

The reason for the whacky naming is historical. Back in the early days of android, devices only had a small amount of user storage. It was generally mounted as "/data" and was probably 1-2 GB in size. This area was limited to storing application specific data (and downloaded applications.) Same examples might be your contacts list, your high score in angry birds, etc.

Many of those phones had a SDCard slot, however. Actually, many of the phones not only had the slot, but came with a card as well. The idea was that you could put music files, photo's, etc on this extra sdcard. A user could easily upgrade the card to whatever size was supported by android. In development terms, this became known as the external sdcard (or external memory) because it was user accessible and not required for the device to function. Traditionally, it was mounted as "/sdcard"

As time went on, more and more phones came with this extra storage. At some point, it was no longer user accessible or removable. However, it was still used the same way and for the same purpose (afterall, why would you need more than 1-2 GB for just app storage?) It's still mounted as /sdcard. When you move applications from "internal storage" to "external storage" you are really moving the bulk of the app data from /data to /sdcard.

Of course, competition goes on, and everyone wants to have the biggest and greatest phone. So, why not do something done before and go BACK to adding a user accessible memory card slot in ADDITION to the existing /sdcard "external memory"? The only problem is that android doesn't really have a proper way to address that, so different phones mount it in different ways. For some, it might be "/sdcard2". For others, it might be mounted as a sub directory of /sdcard (sdcard/ext_storage, etc)

Of course, this causes all kind of problems for programs designed to work on both older phones (where /sdcard was actually external) and newer phones (where /sdcard is built in.)

There are efforts with newer versions of android to try and correct this, but legacy stuff holds us back. In honeycomb (and ICS), "/data" and "/sdcard" are actually the same partition. In fact, "/sdcard" actually points to "/data/media." They use the same space, however. There's no longer a concept of "external memory." (However, its still confusing because programs are usually written to work for many different versions of android.)

Want to make things more confusing? Add in CWM Recovery. In that recovery, "sdcard" refers to the /sdcard partition that is often called "external" memory in android development. Then it refers to "internal sdcard" when talking about any additional memory card that is user accessible. (so "sdcard" is built in memory, and "internal sdcard" is the sdcard that's physically external.)

Confused yet? Me too.

Gary

 

[dandrumheller]

... I'll try to answer the OP question. However, I haven't been around android long enough for this to be an authoritive answer. It's more along the lines of a guess...

The reason for the whacky naming is historical. Back in the early days of android, devices only had a small amount of user storage. It was generally mounted as "/data" and was probably 1-2 GB in size. This area was limited to storing application specific data (and downloaded applications.) Same examples might be your contacts list, your high score in angry birds, etc.

Many of those phones had a SDCard slot, however. Actually, many of the phones not only had the slot, but came with a card as well. The idea was that you could put music files, photo's, etc on this extra sdcard. A user could easily upgrade the card to whatever size was supported by android. In development terms, this became known as the external sdcard (or external memory) because it was user accessible and not required for the device to function. Traditionally, it was mounted as "/sdcard"

As time went on, more and more phones came with this extra storage. At some point, it was no longer user accessible or removable. However, it was still used the same way and for the same purpose (afterall, why would you need more than 1-2 GB for just app storage?) It's still mounted as /sdcard. When you move applications from "internal storage" to "external storage" you are really moving the bulk of the app data from /data to /sdcard.

Of course, competition goes on, and everyone wants to have the biggest and greatest phone. So, why not do something done before and go BACK to adding a user accessible memory card slot in ADDITION to the existing /sdcard "external memory"? The only problem is that android doesn't really have a proper way to address that, so different phones mount it in different ways. For some, it might be "/sdcard2". For others, it might be mounted as a sub directory of /sdcard (sdcard/ext_storage, etc)

Of course, this causes all kind of problems for programs designed to work on both older phones (where /sdcard was actually external) and newer phones (where /sdcard is built in.)

There are efforts with newer versions of android to try and correct this, but legacy stuff holds us back. In honeycomb (and ICS), "/data" and "/sdcard" are actually the same partition. In fact, "/sdcard" actually points to "/data/media." They use the same space, however. There's no longer a concept of "external memory." (However, its still confusing because programs are usually written to work for many different versions of android.)

Want to make things more confusing? Add in CWM Recovery. In that recovery, "sdcard" refers to the /sdcard partition that is often called "external" memory in android development. Then it refers to "internal sdcard" when talking about any additional memory card that is user accessible. (so "sdcard" is built in memory, and "internal sdcard" is the sdcard that's physically external.)

Confused yet? Me too.

Gary

To expand on Gary's comments here a little bit - I came to the SGS2 from an HTC Aria, which was released roughly 18 months ago (I didn't bother to look up the exact date). This was the first 'decent' Android device available on AT&T.

*ducks the flamethrower blasts from backflip owners*

The Aria had no internal SD storage (or more appropriately named EMMC I guess) and stock had 185MB - yes MB - user available app storage on /data. Needless to say, that is pretty severely limiting as far as app storage goes. To make this even more fun, the phone shipped with Android 2.1 (Eclair) which had NO built in provisions for apps to SD.

Thankfully, the dev community got us a FroYo port fairly quickly - so at least we had Android built-in apps to SD at that point. However, if you take a look at any apps you have Apps2SD'ed on your device, you'll see that in many cases, only about half of the storage cost of these apps actually gets moved to your SD card (internal in the case of the SGS2, external on the Aria).

Later, via CM6 and still later in CM7 we got the ability to move apps to an ext partition on SD cards (this may have eventually been possible at some point on HTC based roms as well, I can't recall). The downside to this was the requirement to "trick" the OS into seeing that ext partition on the external SD card as part of the device's internal storage, and it also meant that putting apps there was an all-or-nothing option. Therefore, if you wanted to switch external SD cards, you had to have a linux box to make a copy of the ext partition on one card, and put it on the other card, or all your apps were gone. This was a royal pain in the arse. On the Aria, I typically ran a 1 GB ext partition on an 8Gb card, and stored both my apps and dalvik cache there.

I currently have a bunch of apps on my SGS2 that I never use, but since I'm only using about 500MB of the available 2GB of internal app storage, I dont' bother to delete them. I don't run a ton of games, but the only time I'd think you'd even want to consider the hassle of moving apps to an ext partion on an external card with the SGS2 would be if you are running out of the internal app storage on /data. It's not getting used for anything at all if you move apps to the external card. If you're committed to doing this though, I'd guess if you grabbed a CM7 build for the SGS2 and an app called S2E in the market, you could probably do it.

sorry for the novel.....

DD

 

[DJLittleMike]

... I'll try to answer the OP question. However, I haven't been around android long enough for this to be an authoritive answer. It's more along the lines of a guess...

The reason for the whacky naming is historical. Back in the early days of android, devices only had a small amount of user storage. It was generally mounted as "/data" and was probably 1-2 GB in size. This area was limited to storing application specific data (and downloaded applications.) Same examples might be your contacts list, your high score in angry birds, etc.

Many of those phones had a SDCard slot, however. Actually, many of the phones not only had the slot, but came with a card as well. The idea was that you could put music files, photo's, etc on this extra sdcard. A user could easily upgrade the card to whatever size was supported by android. In development terms, this became known as the external sdcard (or external memory) because it was user accessible and not required for the device to function. Traditionally, it was mounted as "/sdcard"

As time went on, more and more phones came with this extra storage. At some point, it was no longer user accessible or removable. However, it was still used the same way and for the same purpose (afterall, why would you need more than 1-2 GB for just app storage?) It's still mounted as /sdcard. When you move applications from "internal storage" to "external storage" you are really moving the bulk of the app data from /data to /sdcard.

Of course, competition goes on, and everyone wants to have the biggest and greatest phone. So, why not do something done before and go BACK to adding a user accessible memory card slot in ADDITION to the existing /sdcard "external memory"? The only problem is that android doesn't really have a proper way to address that, so different phones mount it in different ways. For some, it might be "/sdcard2". For others, it might be mounted as a sub directory of /sdcard (sdcard/ext_storage, etc)

Of course, this causes all kind of problems for programs designed to work on both older phones (where /sdcard was actually external) and newer phones (where /sdcard is built in.)

There are efforts with newer versions of android to try and correct this, but legacy stuff holds us back. In honeycomb (and ICS), "/data" and "/sdcard" are actually the same partition. In fact, "/sdcard" actually points to "/data/media." They use the same space, however. There's no longer a concept of "external memory." (However, its still confusing because programs are usually written to work for many different versions of android.)

Want to make things more confusing? Add in CWM Recovery. In that recovery, "sdcard" refers to the /sdcard partition that is often called "external" memory in android development. Then it refers to "internal sdcard" when talking about any additional memory card that is user accessible. (so "sdcard" is built in memory, and "internal sdcard" is the sdcard that's physically external.)

Confused yet? Me too.

Gary

Hey Gary,

Makes sense, but at the same time, you can mount a share however you'd like in Linux and therefore should be able to do the same in Android. Phones that have two SD cards obviously are able to mount both, and it would make sense to have software use Android's internal mapping for them.

So I guess the real answer is a) I can't move apps to the *external* SD card, b) the mount points differ by phone manufacturer/ROM used, and c) because there is no standard, it's impossible to do everything I want automatically, but for most things I can still move them myself. Does that sound about right?

 

[Stevenrogers_420]

We need to mount another 16GB card and figure a way to RAID em for faster access..
Edit: yeah been drinking again...
Sent from my SAMSUNG-SGH-I777 using xda premium

 

[Entropy512]

Want to make things more confusing? Add in CWM Recovery. In that recovery, "sdcard" refers to the /sdcard partition that is often called "external" memory in android development. Then it refers to "internal sdcard" when talking about any additional memory card that is user accessible. (so "sdcard" is built in memory, and "internal sdcard" is the sdcard that's physically external.)

Confused yet? Me too.

Gary

This was mainly due to the fact that the Android standards got firmed up during the development of CWM 5.x (which is where support for the "internal" sdcard was first implemented)

Initially, CWM only supported one sdcard - and nearly all integrators chose this to be the internal memory.

Then later in 5.x, CWM added support for external/internal sdcards, following the new Android standard of internal on /emmc and external (but not labeled as such) on /sdcard

The problem is - almost all CWM implementations at this point used /sdcard for the internal mount point.

So the choice when I upgraded to CWM 5.0.2.7 was:
Leave things swapped as is and have the "internal" mislabeled (I had not yet figured out how to build CWM from source at this point)
Swap things and have tons of people be like, "WHERE MAI BACKUPZ?"

I'm thinking of doing the swap next time I update CWM - which might be later this weekend.

 

[garyd9]

I'm thinking of doing the swap next time I update CWM - which might be later this weekend.

I'd suggest not directly swapping. The confusion for people switching between different devices with CWM Recovery would be annoying. (I could even see it confusing an experienced user when they jump between different devices that both have CWM Recovery, but use opposite labels.)

Instead of redefining existing terms, it might make things easier to understand if you replace the string "internal sdcard" with a different, but non-conflicting term, such as: "microSD card" or "replaceable sdcard." When a user sees two options, such as "backup to sdcard" and "backup to replaceable sdcard", it's more obvious which one is which. (Of course, "backup to built-in memory" would be even more clear for the former option.)

Take care
Gary

 

[BadElf]

Great info, thanks to all. Now let me throw in another term, "USB Storage." I ran across this in file manager after I had done a complete factory wipe, cache wipe, format, et al. In "USB Storage" was several files I had thought were on the 16Mb Class 6 microSDHC I had just formatted. So, where does this fit in the grand scheme?

 

[DJLittleMike]

Great info, thanks to all. Now let me throw in another term, "USB Storage." I ran across this in file manager after I had done a complete factory wipe, cache wipe, format, et al. In "USB Storage" was several files I had thought were on the 16Mb Class 6 microSDHC I had just formatted. So, where does this fit in the grand scheme?

Oo! Oo! I can actually answer this one. USB storage is the "internal" SD card. I know this because I added labels to them in Windows and tested this myself. So you have 2GB of internal storage (not an SD card) SD Card (the user-replaceable one) and then USB storage (the internal SD card.)

Yes, very confusing, and I'm glad I made this thread, because I found out I'm not an idiot. Okay, I still may be but not because I don't know the difference and/or usage. It seems there are at least a few others that got confused as well.

Entropy, so the naming convention is controlled by kernel and you can name that whatever you want? I'm for the switch, but maybe make two versions available? One with the old naming convention and one with the new. For the new, my suggestion would be to name all three something descriptive. IE:

internal storage = internal storage (it's 2GB, I don't think people confuse this much)
USB storage = permanent SD card or non-removable SD card
SD Card = external SD card or even removable SD card

I think that should be clear enough. One is internal storage... not an SD card. Out of the two SD cards, one is removable and the other is not. Simple enough.

 

[tora67]

resurrecting a dead thread

I'm curious why this has not been brought up...It appears with Custom ROMs we can have apps install direct from Play store to removable sd. We just need to properly partition the removable sd : http://forum.xda-developers.com/showthread.php?t=1158993 .

I am actually looking into this practice. Does Shostock v4 not support such thing?
Also, folks who do partition their removable sd seem to favor amonRA over CWM...

Can someone shed some lights on this?

 

[Pirateghost]

I'm curious why this has not been brought up...It appears with Custom ROMs we can have apps install direct from Play store to removable sd. We just need to properly partition the removable sd : http://forum.xda-developers.com/showthread.php?t=1158993 .

I am actually looking into this practice. Does Shostock v4 not support such thing?
Also, folks who do partition their removable sd seem to favor amonRA over CWM...

Can someone shed some lights on this?

For starters that's a completely different device. Different manufacturer. HTC does things differently. They used to ship their phones with little storage like 4gb for OS and app install. They didn't provide gobs of onboard storage like Samsung.

Secondly that thread is over a year old.

AmonRA isn't available on this device. Again completely different devices, different methodologies.

The gs2 has plenty of storage and app install space available. Why does everyone think that installing your apps to external SD is a good thing?

Sent from my Nexus 7 using Tapatalk 2

 

[tora67]

we want more space

I bet many like the OP would like apps and app data stored on their removable sd especially nowadays you can get a class 10 sd for cheap.

 

[Pirateghost]

Have you noticed how many apps will not work at all with apps on the SD card?

If you have the apps installed on the sdcard and you plug into your computer the apps become unavailable and Widgets for those apps stop working.

Sent from my Galaxy Nexus using Tapatalk 2

 

[Simba501]

. . . Widgets for those apps stop working.

And I'm pretty sure you have to re-add them.