realm-java: io.realm.exceptions.RealmFileException when launching application

I have researched many and many times about this issue but I have not found any solution. I am implementing an Android application with Realm Android 3.0 and using Fabric to find out crash report. Below is Realm initialize code in Application class:

 Realm.init(this);
        RealmConfiguration config = new RealmConfiguration.Builder().name(REALM_SCHEMA_NAME)
                .schemaVersion(REALM_SCHEMA_VERSION)
                .migration(new Migration())
                .build();
        Realm.setDefaultConfiguration(config);
        Realm realm = Realm.getDefaultInstance(); // Automatically run migration if needed
        realm.close();

I get many crash report from Fabric related with io.realm.exceptions.RealmFileException such as:

Unable to open a realm at path ‘/data/data/com.xxx/files/xxx.realm’: Incompatible histories.
Unable to open a realm at path ‘/data/data/com.xxx/files/xxx.realm’: bad realm file header (#3). (bad realm file header (#3))
Unrecoverable error. mmap() failed: Out of memory size xxx
etc …

So, can you tell me the reason of this issue? Thank you.

About this issue

Original URL
State: closed
Created 7 years ago
Comments: 73 (34 by maintainers)

Most upvoted comments

Only Realm.getInstance() . Realm.init() just load and setup the Realm library, so it isn’t connected to opening any files.

cmelchior on Jan 17, 2018

Realm.getInstanceAsync() + Realm.Builder.compactOnLaunch() will be the my choice if I want to do that. But it depends on your use case if you can manage the app’s life cycle well.

beeender on Dec 14, 2017

compact() should reclaim disk space which is not being used including the case you mentioned. See https://realm.io/docs/java/latest#faq-large-realm-file-size

compact operation may take some time to finish depends on how much valid data stared. Consider to use those APIs

https://realm.io/docs/java/4.3.1/api/io/realm/RealmConfiguration.Builder.html#compactOnLaunch--

https://realm.io/docs/java/4.3.1/api/io/realm/Realm.html#getInstanceAsync-io.realm.RealmConfiguration-io.realm.Realm.Callback-

beeender on Dec 14, 2017

@jollyjoker992 Compacting a Realm will removed other versions and other unused space in the Realm file. Most databases have such a function (in PostgreSQL it is called VACUUM). We don’t support online compaction so doing it a launch after the app has been killed sounds like a good time to do it.

kneth on May 9, 2017

@jollyjoker992 No exact date but we will probably do a release in a week or two (we don’t have fixed date as support load or critical bugs are hard to predict).

kneth on Apr 28, 2017

@jollyjoker992 With #4559 merged, you can try a snapshot release and see if it solves your issue.

kneth on Apr 27, 2017

A possible fix for I think this error is being investigated in https://github.com/realm/realm-java/pull/4559

Zhuinden on Apr 27, 2017