Improve performance on Entity Framework Code-First
Code-First can run into some serious performance issues with LazyLoading. I would like to see Code-First (and its lazy loading feature) as a viable option for developing high performance web applications.
Please follow the links Rowan mentioned in his comments.
Rowan Miller commented
We are continually working to improve the performance of Entity Framework, we recently released Beta 2 of EF6 which includes some big performance improvements - http://blogs.msdn.com/b/adonet/archive/2012/12/10/ef6-alpha-2-available-on-nuget.aspx.
If you have particular scenarios that you want to see improved then feel free to log a detailed report in our public issue tracker - http://entityframework.codeplex.com/WorkItem/Create.