I want to know the exact date the Entity Framework 7.0 will be released? Also, Will be a performance difference between EF6.0 and EF 7.0
ASP.NET Core 1.0 and EF Core 1.0 will be released end of June 2016, accroding to this blog post on the .NET blog: https://blogs.msdn.microsoft.com/dotnet/2016/05/06/net-core-rc2-improvements-schedule-and-roadmap/
And yes, there will be a performance difference, as EF Core is esentially a brand new product, that shares name (and some APIs) with Entity Framework 6.x and earlier.
You can see some performance demos here: https://channel9.msdn.com/Events/Build/2016/B852