Core Data Migration really Slow, Why does it happen at all?

Question

I'm developing a desktop Mac OS X App that saves its very simple data into SQLite with Core Data and a companion mobile App for iPhone that simply needs to read data from the desktop App. Although they share the same Managed Object Model when I load the SQLite database on the mobile app the data takes several seconds to migrate the data. I really would like to avoid this long wait as it appears linearly related to the size of the SQLite file.

Why is data from the same Managed Object Model even needing to migrate at all?

Does anyone know of a way to avoid needing to migrate?

Answer 1

I've discovered what was causing this problem. Although it is probably very obvious I'll relate it so hopefully no one else will make this mistake...

I had two distinct Managed Object Models in my project. Having more than one seems to force Core Data to try migrating to figure out which data matches with which MOM.

As a solution I was able to manually merge the models so both data sources can be represented with the same MOM.