Memory issues migrating large CoreData datastores on iPhone

Question

My app has a potentially very large CoreData datastore underneath it (could easily be upwards of 30MB). I\'ve started noticing memory issues when using the automatic migrat

Answer 1

I was able to get around this in the short-term by leveraging "lightweight" migration, as described in http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/CoreDataVersioning/Articles/vmLightweight.html#//apple_ref/doc/uid/TP40008426-DontLinkElementID_1.

The trick is to pull the NSMigrationManager subclass that is specifically for SQLite store types when you're manually invoking the migration, as shown in the last code sample on that page.

This isn't a general-purpose fix though since it only works if the schema change in your datastore is simple enough that lightweight migration is possible. Still waiting to hear back from Apple as to what the recommended solution is when you're dealing with a non-trivial mapping.