I have a realm object with ~30 fields, after adding and removing several objects it seems that realm takes up quite a bit amount of space. The size of the allocated space seems to grow somewhat exponentially:
10*(add 100 + remove all) = 4 mb Data
15*(add 100 + remove all) = 33 mb Data
20*(add 100 + remove all) = 91 mb Data
25*(add 100 + remove all) = 179 mb Data
The file itself in data\\data\\app_folder\\files\\default.realm is 200 mb at this point.
Now this serious issue might be because i am not doing something properly. Before every insertion i do
Realm realm = Realm.getInstance(context);
realm.beginTransaction();
realm.where(RealmSubmission.class).findAll().clear();
// if i use realm.allObjects(RealmSubmission.class).clear(); the leak is even bigger, i get to 170mb Data with 20*(add 100 + remove all) even though both calls do the same by looking at their semantics.
realm.commitTransaction();
Adding items into realm looks like this:
for (Submission submission : submissionList){
realm.beginTransaction();
RealmSubmission realmSubmission = realm.createObject(RealmSubmission.class);
RealmObjectUtils.copySubmission(realmSubmission, submission);
realm.commitTransaction();
}
Any ideas?
I've made a simple method to delete the realm database file when a migration exception occur (for dev). It also return a new realm instance to prevent any issue.
public Realm buildDatabase(){
RealmConfiguration realmConfiguration = new RealmConfiguration.Builder(this).build();
try {
return Realm.getInstance(realmConfiguration);
} catch (RealmMigrationNeededException e){
try {
Realm.deleteRealm(realmConfiguration);
//Realm file has been deleted.
return Realm.getInstance(realmConfiguration);
} catch (Exception ex){
throw ex;
//No Realm file to remove.
}
}
}
I tried replicating with a small model class (one String, one int) with no success.
Do you use Links and/or LinkLists in your model? Can I take a look at it?
One reason might be in the case you have for example a Person class that has a RealmListdogs field. When you delete all the elements of the Person type the Dogs are right now retained in the database.
EDIT: After you provided the data I tried with a bit of dummy data:
Realm.deleteRealmFile(this);
Realm realm = Realm.getInstance(this);
File realmFile = new File(this.getFilesDir(), "default.realm");
long tic = System.currentTimeMillis();
for (int i = 0; i < 25; i++) {
for (int j = 0; j < 100; j++) {
realm.beginTransaction();
TestObject testObject = realm.createObject(TestObject.class);
testObject.setApprovedBy("Approver_" + j);
testObject.setAuthor("Author_" + j);
testObject.setBannedBy("Banner_" + j);
testObject.setClicked(j % 2 == 0);
testObject.setCommentCount(j);
testObject.setCreated(System.currentTimeMillis());
testObject.setCreatedUTC(j*7);
testObject.setEdited(j % 3 == 0);
realm.commitTransaction();
}
realm.beginTransaction();
realm.where(TestObject.class).findAll().clear();
realm.commitTransaction();
Log.i(TAG, "Size: " + realmFile.length());
}
long toc = System.currentTimeMillis();
Log.i(TAG, "Time: " + (toc - tic));
But I still cannot reproduce:
10-08 14:39:01.579 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 24576
10-08 14:39:01.999 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 24576
10-08 14:39:02.409 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 24576
10-08 14:39:02.809 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 24576
10-08 14:39:03.209 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 24576
10-08 14:39:03.649 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:04.049 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:04.449 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:04.839 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:05.329 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:05.709 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:06.259 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:06.689 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:07.109 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:07.589 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:08.019 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:09.129 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:09.729 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:10.169 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:10.669 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:11.049 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:11.449 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:11.849 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:12.269 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Size: 49152
10-08 14:39:12.269 29233-29233/myapp.realm.io.sizeleak I/REALMTEST﹕ Time: 11265
The size doubling is expected because of fragmentation, but I still see nothing that can suggest your experience.
The timing is high because of the large number of transactions. Batching them together would increase performance considerably:
10-08 14:45:25.009 31593-31593/myapp.realm.io.sizeleak I/REALMTEST﹕ Time: 408
Delete all objects from Realm database:
realm.executeTransaction(new Realm.Transaction() {
@Override
public void execute(Realm realm) {
realm.deleteAll();
}
});
You should delete the Realm file. Until first time you use Realm no file is created. That's what you want:
try {
Realm.deleteRealmFile(context);
//Realm file has been deleted.
} catch (Exception ex){
ex.printStackTrace();
//No Realm file to remove.
}
Be sure no realm instance is been used.
ok old stuff but anyway. i started to use Realm in android now and i'm still checking it out but for past experiences using OO databases since transactions can be cancelled the more transactions you do the bigger the footprint you will leave, in order to cancel a copy of the state must exist but you are commiting right, from my experience the prob is that some databases do not discard the transactions right away after commiting but this is behind the scene stuff (i cannot confirm this, just talking about previous experiences that i had with other OO databases where you could config these settings)
another thing that i noticed in both codes here is that none closes the instance and so (also speculating) maybe the Realm of each commited transaction is not being able to get GC
again just speculating hope it helps
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