Android system cant start because of "No space left on device"? I ran my app, which communicated with my server in every 5 minutes. 2 days later I can't turn on my tablet, because it stops at the boot image.
I'm getting all kinds of error in logcat like this.
My app did not use any database, so I don't know what went wrong, and how can I solve it..

E System  : ******************************************
E System  : ************ Failure starting system services
E System  : java.lang.RuntimeException: Failed to boot service com.android.server.devicepolicy.DevicePolicyManagerService$Lifecycle: onBootPhase threw an exception during phase 480
E System  : Caused by: android.database.sqlite.SQLiteDiskIOException: disk I/O error (code 4874)

W SystemServer: ***********************************************
E SystemServer: BOOT FAILURE making Lock Settings Service ready
E SystemServer: android.database.sqlite.SQLiteDiskIOException: disk I/O error (code 4874)


I SystemServiceManager: Starting phase 480
E SQLiteLog: (4874) os_unix.c:29945: (28) write(/data/system/locksettings.db-shm) -
E SQLiteLog: (4874) disk I/O error
E SQLiteLog: (4874) os_unix.c:29945: (28) write(/data/system/locksettings.db-shm) -
E SQLiteDatabase: Failed to open database '/data/system/locksettings.db'.
E SQLiteDatabase: android.database.sqlite.SQLiteDiskIOException: disk I/O error (code 4874): , while compiling: PRAGMA journal_mode
E SQLiteOpenHelper: Couldn't open locksettings.db for writing (will try read-only):
E SQLiteOpenHelper: android.database.sqlite.SQLiteDiskIOException: disk I/O error (code 4874): , while compiling: PRAGMA journal_mode


D AndroidRuntime: Shutting down VM
E AndroidRuntime: *** FATAL EXCEPTION IN SYSTEM PROCESS: main
E AndroidRuntime: java.lang.RuntimeException: Failed to boot service com.android.server.devicepolicy.DevicePolicyManagerService$Lifecycle: onBootPhase threw an exception during phase 480

DropBoxManagerService: java.io.IOException: write failed: ENOSPC (No space left on device)


So how Can I figure out what allowed my space, and how can I resolve this problem, and start the device.
Currently I can't even use ADB commands because the device don't even start...
Most likely your application has either filled up the /data partition or (if your tablet is rooted) even the system partition. Likely suspects are log files and SQlite databases growing infinitly. 

A communication every 5 minutes over 2 days means 576 communications - if every communication uses up a MB of storage, you have used up more than half a Gigabyte.


Adapt your application to never ever write to system
Adapt your application to keep a firm hand on disk usage on data
Adapt your application to stop if less than half a Gig of storage is available


Then factory-reset your tablet via recovery and try again.