Database Develop

[Q] putting apps in /system/app, good or bad?

Hi, I've been putting some of my apps apks in /system/app, so that I have more free space in /data.
Mostly I just put apps there that I know I will never need to uninstall, like TiBackup, LauncherPro etc. When those apps update, I just manually move the newer apk into /system/app.
Question: Is it wrong to fill up /system to almost-full?
I know it's mounted read-only during normal use, so nothing else can write to it anyway.

Yup, I'd like to know tha answer to this question too!

I have heard of it being done quite abit. So it can't be that bad.

Yeah, it can't be that bad. But what if you filled it to 100%, is that bad?
Cache and data are housed in separate partitions as far as I know. So, I believe it's ok to fill it up completely, since most other things don't need write access to /system partition anyway. If it's not being written to during normal operation, then any free space on /system is basically wasted.
But I'd still like to hear from someone more knowledgeable if it is indeed fine to fill up the /system partition. Or if it's better to leave a certain amount of space, and how much space is recommended.

It depends on the ROM. If you're using CM, apps in the /system partition stores it's dalvik-cache in the /cache partition. So, if I am correct, more apps in the /system means less /cache space.

I tried putting LauncherPro in /system/apps and then removing it from /data/apps, but with no luck - it kept force closing on launch not ideal for a launcher! I haven't yet figured out why it wouldn't work, but I'm sure I'll get there in the end.
SF

geevee11 said:
It depends on the ROM. If you're using CM, apps in the /system partition stores it's dalvik-cache in the /cache partition. So, if I am correct, more apps in the /system means less /cache space.
Click to expand...
Click to collapse
On CM6, /cache is a different partition than /system, so it shouldn't affect cache space.
I'll observe the free space for a few days without adding additional apps on /system. Right now, I have 15MB free on /system, and 39MB free on /cache. I'll report back in a while.

r8dhex said:
On CM6, /cache is a different partition than /system, so it shouldn't affect cache space.
I'll observe the free space for a few days without adding additional apps on /system. Right now, I have 15MB free on /system, and 39MB free on /cache. I'll report back in a while.
Click to expand...
Click to collapse
I was talking about the dalvik-cache. Even if you install apps in the /system partition, it'll still have the dex files. So the more apps you put in your /system partition, the more your /cache will fill up = less ram.

I found out that apps in /system couldn't be updated through the market.
For instance: the facebook app that comes installed with google apps package of CM6 is installed in the /system dir of the phone. When I tried to update it through market it would fail every time. Once I deleted the app from /system and rebooted the phone, updating (installing) the app from market went fine.

[Q] How to use /cache for apps

Some of you suggested using the cache partition for app cache - but when I use 'df' in Terminal Emulator it states that only 13604K of my 108544K cache partition are free.
When 'ls'-ing the /cache partition it lists files named "downloadfile.apk" to "downloadfile-34.apk".
Is this some OTA update?
That'd be strange, since the last (2.2.1) update came via PC only and i wiped everything that could be wiped via the recovery menu.
Furthermore the the creation dates of the .apks range from may to a few days ago.
But when I try to open them using Root Explorer it says "Error parsing package" and opening them via "View" gives me a blank screen.
Please enlighten me.
Thanks in advance

Those are temporary downloads from the market. Updates etc.

Does it only remove them on demand?
So I can remove them savely to make room for my appcache?

Once they're installed you can safely remove the apks in /cache

I was able to gain some space by wiping the dalvik cache so I'm gonna delay trying to use /cache
But I have one more question: several sources claim that using /cache for app-cache incompatible with App2SD - is that true?

I'm afraid I need some more clarification so I'm gonna push this thread...
I checked the sizes of my dalvik cache folder and /cache partition
df states that /cache has a total size of 108544K, 93793K used by .apk files I cannot open with Root Explorer and 13364K free
In my /data/dalvik-cache folder theres files summing up to 100956K
So they would barely fit in /cache if I delete all the .apks
I'm not sure if that would be a good idea...
Any suggestions?

Titanium Backup Dalvik Integration

So TiBu just added an option to integrate the system dalvik cache to the ROM. Does this move it to /system or what? Because I don't want to integrate this and lose what little space is left on /system.
Sent from my Xoom using xda premium

d3athsd00r said:
So TiBu just added an option to integrate the system dalvik cache to the ROM. Does this move it to /system or what? Because I don't want to integrate this and lose what little space is left on /system.
Sent from my Xoom using xda premium
Click to expand...
Click to collapse
I wouldn't do it.

d3athsd00r said:
So TiBu just added an option to integrate the system dalvik cache to the ROM. Does this move it to /system or what? Because I don't want to integrate this and lose what little space is left on /system.
Sent from my Xoom using xda premium
Click to expand...
Click to collapse
Hi, same question here. What does that mean. anyone?

I run script in etc/ init.d to move dalvik cache to cache folder.
I have all the permission checked.
#!/system/bin/sh
echo "++++ DALVIK 2 CACHE STARTING ++++"
if [ ! -d /cache/dalvik-cache ]
then
mkdir /cache/dalvik-cache
chown 1000:1000 /cache/dalvik-cache
chmod 775 /cache/dalvik-cache
fi
if [ -L /data/dalvik-cache ]
then
rm -f /data/dalvik-cache
mkdir /data/dalvik-cache
chown 1000:1000 /data/dalvik-cache
chmod 775 /data/dalvik-cache
elif [ ! -d /data/dalvik-cache ]
then
mkdir /data/dalvik-cache
chown 1000:1000 /data/dalvik-cache
chmod 775 /data/dalvik-cache
elif [ -d /data/dalvik-cache ]
then
for filename in /data/dalvik-cache/*
do
if [ -L $filename ]
then
rm -f $filename
fi
done
mv /data/dalvik-cache/* /cache/dalvik-cache/
fi
mount -o bind /cache/dalvik-cache/ /data/dalvik-cache/

Yeah I'm reviving thks thread because I'm shocked at the responses given to a legit question. No one ever tried to explain and instead took their time to say "don't try it". It shouldn't hurt anything trying it out as long as you have a back up . in fact on my G2 of happily go do it without a backup.
I'm not 100% what it does but a quick search where people without complexes answers should give you the answer. There must be a purpose behind it as it's still an option to this very day. In thinking it moves dalvik to either /system or somewhere else off the top of my head. I used to know but moving dalvik hasn't been an issue really anymore. Here to got dog slap the naysayers I'll click the option before refresingy memory and tell ya where it's moved to. Well yell others since this is the first search result to show on google when searching the topic so even though it's dear question is still relevant. See, back in the day when we ran on tiny amounts of storage space a lot of is moved /data/dalvik-cache elsewhere and left a symlink there so apps could find it and so we could free more space up for apps.
People need to learn that xda posts are often the top Google search results and need to act accordingly and professional (well as professional as fun loving devs get ). Let me integrate for everyone and I'll report back with the the exact location. Now his advice though on not doing is sound because of you don't know what you're doing or yow to undo it then you need to do more researching but a real answer should have acompanied it. If i was up (which in won't do) I know how to fix the issue in a heartbeat.
Edit: Appears to move certain apks into /system/app toake use or all the space there. I move 76 files and no issues. In the day there were many horror stories but nothing that had. Just missing apks from what was moved since not all apks liked being system apps.
Solution is to find apks in /system/app and delete (or use command line uninstall feature) and reinstall. Undoing the integration within TA might also work, but these newer phones arent as bad. Least not the G2 as all my apps are there. Each their own

Odex for more space, not really.
This thread may have been born dead, but for the same reasons as the last post, needs more input:
The Titanium Backup option to integrate system dalvik into ROM will free some space on your internal sd storage partition, but use disproportionally more space on the system partition. As far as total internal storage it is a loss, but the common ailment of legacy devices is to run out of internal sd space as apps are installed.
Example: I started with 108 MB of free space on my system, and 2.1 GB of free space on my internal storage. TiBk offered 94 integrable files totaling 71 MB. After integration, I only have 37 MB free space on the system, and 2.15 GB free space on the internal storage. So even though I gained 41 MB for user apps, I actually lost 30 MB in total to odexing on my system.
A more efficient method for gaining internal sd space would be to conversely shrink the system partition while enlarging the internal data/media partition. But this isn't always possible or too extreme a measure for many users.
In addition to moving data from one internal partition to the other, all the newly integrated ROM files will be odexed. This will speed up the the first boot and boot after clearing dalvik cache, as the odexed apps are already optimized to the ROM. In addition, the odexed apps will launch a little faster and technically have a performance edge, though commonly reported as 'not noticeable'.
After integrating the system Dalvik into the ROM, it can just as easily be deintegrated with the next settings option in TiBk. This is necessary before applying certain themes and mods requiring deodexed apks. Then you would ideally integrate and odex again.

MidnightHarvester said:
Undoing the integration within TA
Click to expand...
Click to collapse
Did you mean TB

I have used this on my S4...I have 1.2gb of free space in my system/Rom partition so it would be rude not to.. I moved around 500mb from internal SD card... All worked fine...
But now using a different custom rom, Kernel and different version of TB... It won't integrate the dalvik any more... Just says 278 item failed to integrate.... Im guessing TB can't write to the system/rom partition for some reason?? I think I may have been on a kit kat Rom when it worked for me..

[Q] Darktremor apps2sd problem

I followed the instructions on this site and did a 2GB partition. I downloaded the a2sd app from the Android Market and moved the Dalvik cache to SD-EXT. It seems to be working because on the A2SDGUI app, it is showing "Apps are on SD!" and "Dalvik Cache on SD-EXT".
I seem to be able to download a lot of small apps from the Android Market without any problem. However, when it comes to larger apps such as Angry Birds and Pocket Legends, this is the error I'm receiving: There is insufficient space on the device.
I have a Samsung 8GB Class 6 micro-SD Card with almost 2GB free space left. Here is a Screenshot of the System Info on the A2SDGUI app. I'm supposed to be having a 2GB partition but it is not being recognized for some reason. But I do not know if that is normal.
I'm using Squadzone's latest CM7 RC5 with all the 3 updates.

That's because your /cache partition stays the same - ~25MB.
1) You can use this script: http://dl.dropbox.com/u/45530921/30mountcache.txt
(Put it in /system/etc/init.d/ and set persmissions, allow execute - do backup... just in case!)
2) Or you can use Amarullz or Ungaze scripts.

TheWhisp said:
1) You can use this script: http://dl.dropbox.com/u/45530921/30mountcache.txt
(Put it in /system/etc/init.d/ and set persmissions, allow execute - do backup... just in case!)
Click to expand...
Click to collapse
So, if I use the script you provided, I will not have to disable Darktremor's a2sd and reflash the rom?
If yes, I will have to:
1) Download the "30mountcache.txt" to sd card.
2) Move to /system/etc/init.d
3) Rename it to just "30mountcache".
4) Set permission for Owner/Group/Others to execute.
5) Reboot.
I'm not very good at this.

30mountcache will not disable your a2sd. Put it there, rename, permissions and done

It's working. Thanks.

[MOD][GUIDE][ROOT EXPLORER] Free up data space. Move Dalvik Cache to System.

GuYWith a deodexed and de-bloated Samsung Rom we have 500mb plus of free space on System partition which is wasted space.
I just tried something to free up some space for shared data/sdcard partition by moving Dalvik Cache from /data to /system then creating a folder link back in data to keep original location settings.
Took 30 seconds and freed up 260mb! This is what you do:
1. Using root explorer or similar. Go to /Data.
2. Navigate to "Dalvik-Cache" directory. Long press on it and select "move".
3. Navigate back to root directory and then to /System.
4. Paste the directory you must select rw first top right hand corner. It will take a minute to copy.
5. Now long press on the moved Dalvik-Cache directory in /System and select "Link to this folder" option.
6. Navigate back to /Data and paste the link.
7. Done! You now have moved the Dalvik-Cache location to unused space on System partition and left a sym-linked directory so Android thinks nothing has changed!
Note!: If you wipe Dalvik Cache from recovery a new directory will be recreated in Data and your moved directory in System will no longer be used it will just sit in System taking up space.
AFTER A DALVIK CACHE WIPE FROM RECOVERY YOU MUST DELETE THE DIRECTORY YOU CREATED IN SYSTEM AS IT IS NO LONGER USED. SIMPLY REPEAT THE ABOVE STEPS TO ACTIVATE THE MOD AGAIN.
Good luck. A REAL Dev could you please turn this into a CMW zip with the reverse undo counterpart to be flashed before a Rom upgrade.
UPDATE: looking at the link posted by a helpful person below (thanks!) I think we need to make /system mount as rw for this to work. Please help develop this idea more if anyone can help thanks
Sent from my GT-I9300 using xda premium

Is it work on cm10? I have over 1gb free on system partition

jnr21 said:
Is it work on cm10? I have over 1gb free on system partition
Click to expand...
Click to collapse
I'M not sure haven't used cm10 yet but it should do. Just discovered a Dalvik Cache wipe from recovery recreates the directory in Data to the MOD needs to be repeated after this... makes it very safe to try on cm10!
I'm hoping a real Dev can take this idea and bake it into to custom Rom's and find more data we can move to free up more space
Sent from my GT-I9300 using xda premium

Hi,
Maybe it's possible to do this via init.d script? It will be more convenient.
It's possible via init.d script to move dalvik-cache to /cache for example... so...
Just a thought or simply move it to /cache.
EDIT:found this: http://petermolnar.eu/linux-tech-coding/how-to-move-dalvik-cache-to-system-partition-in-android/

Is this similar to the function "Integrate sys Dalvik into ROM" from Titanium Backup?

[email protected] said:
Is this similar to the function "Integrate sys Dalvik into ROM" from Titanium Backup?
Click to expand...
Click to collapse
Yeah I guess it is but if you do it through titanium the Dalvik Cache files are put with their apk files so wipe Dalvik Cache in recovery no longer works... Not 100% sure this is right tho
Sent from my GT-I9300 using xda premium

viking37 said:
Hi,
Maybe it's possible to do this via init.d script? It will be more convenient.
It's possible via init.d script to move dalvik-cache to /cache for example... so...
Just a thought or simply move it to /cache.
EDIT:found this: http://petermolnar.eu/linux-tech-coding/how-to-move-dalvik-cache-to-system-partition-in-android/
Click to expand...
Click to collapse
Yeah should be possible. I think a CWM zip would be best along with an undo version. I now have /Data/app directory moved so before a Rom update or nandroid backup it will be necessary to undo the move. I'll see if I can work out how to do this. Hopefully someone could help out. I'M not code literate yet lol!
Sent from my GT-I9300 using xda premium

if u wanna free up the /data partition, it is a good and proper way to move the dalvik-cache elsewhere. but IMHO, the /system partition is not a good place to move to since by design the system partition is not suppose to have any frequent or unnecessary read write and thus it is ro by default. the other reason is its importance since it is the core part of the system. you can afford to pay for a corrupted data or cache partition but not the system partition since as long as the system files are save the whole system can be rebuilt in case of data loss etc
i am not against this trick and i only want to tell you my opinions. so if possible i would recommend u to put the dalvik cache somewhere else like the cache partition

ykk_five said:
if u wanna free up the /data partition, it is a good and proper way to move the dalvik-cache elsewhere. but IMHO, the /system partition is not a good place to move to since by design the system partition is not suppose to have any frequent or unnecessary read write and thus it is ro by default. the other reason is its importance since it is the core part of the system. you can afford to pay for a corrupted data or cache partition but not the system partition since as long as the system files are save the whole system can be rebuilt in case of data loss etc
i am not against this trick and i only want to tell you my opinions. so if possible i would recommend u to put the dalvik cache somewhere else like the cache partition
Click to expand...
Click to collapse
Yes I've discovered that it's prob not a good idea to leave System rw.... all that wasted space tho
Sent from my GT-I9300 using xda premium

rlorange said:
Yes I've discovered that it's prob not a good idea to leave System rw.... all that wasted space tho
Sent from my GT-I9300 using xda premium
Click to expand...
Click to collapse
u can resize the system partition, and then reassign the disk space freed up to other partitions
NOTE: this is risky and may brick your phone
if you r interested, you can get some more info in my blog posts (based on I9000)
Free more available disk space from NAND - PART I
Free more available disk space from NAND - PART II
freeNANDmod - get more space from NAND - PART III
freeNANDmod - get more space from NAND - PART IV

- symbolic linked dalvik-cache directory may cause issues in some application, use the bind mount instead of this
- titanium backup feature (integrate dalvik-cache to rom) is not mean what you think. it is not for moving dalvik-cache to the system partition
edit: i writed a script what can do exactly what we need.
auto check the dalvik-cache already moved to the cache directory, if yes bind mount the directory. if not, moved the cache then bind mount
you can adjust the cache and the data partition in the beginning of the file, dont touch anything else! default is defined for the SGS3
log file is /cache/dalvik_mover.log
after a full cache wipe the script will be move the dalvik cache after the next reboot
just unzip and put this file to the /system/etc/init.d/ folder
then set the permission to 0755
reboot
this script is not using the system partition, so no need to remount the system as r/w. its used the cache partition what have more free space anyway and always writeable.
and the bind mount method is compatible with everything.

rlorange said:
GuYWith a deodexed and de-bloated Samsung Rom we have 500mb plus of free space on System partition which is wasted space.
I just tried something to free up some space for shared data/sdcard partition by moving Dalvik Cache from /data to /system then creating a folder link back in data to keep original location settings.
Took 30 seconds and freed up 260mb! This is what you do:
1. Using root explorer or similar. Go to /Data.
2. Navigate to "Dalvik-Cache" directory. Long press on it and select "move".
3. Navigate back to root directory and then to /System.
4. Paste the directory you must select rw first top right hand corner. It will take a minute to copy.
5. Now long press on the moved Dalvik-Cache directory in /System and select "Link to this folder" option.
6. Navigate back to /Data and paste the link.
7. Done! You now have moved the Dalvik-Cache location to unused space on System partition and left a sym-linked directory so Android thinks nothing has changed!
Note!: If you wipe Dalvik Cache from recovery a new directory will be recreated in Data and your moved directory in System will no longer be used it will just sit in System taking up space.
AFTER A DALVIK CACHE WIPE FROM RECOVERY YOU MUST DELETE THE DIRECTORY YOU CREATED IN SYSTEM AS IT IS NO LONGER USED. SIMPLY REPEAT THE ABOVE STEPS TO ACTIVATE THE MOD AGAIN.
Good luck. A REAL Dev could you please turn this into a CMW zip with the reverse undo counterpart to be flashed before a Rom upgrade.
UPDATE: looking at the link posted by a helpful person below (thanks!) I think we need to make /system mount as rw for this to work. Please help develop this idea more if anyone can help thanks
Sent from my GT-I9300 using xda premium
Click to expand...
Click to collapse
Yes, to get this working you need a system mounted Always in r/w.
So i suggest you to move dalvik on cache partition.
And it's better to do the mod inside ramdisk

vadonka said:
- symbolic linked dalvik-cache directory may cause issues in some application, use the bind mount instead of this
- titanium backup feature (integrate dalvik-cache to rom) is not mean what you think. it is not for moving dalvik-cache to the system partition
edit: i writed a script what can do exactly what we need.
auto check the dalvik-cache already moved to the cache directory, if yes bind mount the directory. if not, moved the cache then bind mount
you can adjust the cache and the data partition in the beginning of the file, dont touch anything else! default is defined for the SGS3
log file is /cache/dalvik_mover.log
after a full cache wipe the script will be move the dalvik cache after the next reboot
just unzip and put this file to the /system/etc/init.d/ folder
then set the permission to 0755
reboot
this script is not using the system partition, so no need to remount the system as r/w. its used the cache partition what have more free space anyway and always writeable.
and the bind mount method is compatible with everything.
Click to expand...
Click to collapse
thank you very much works perfect