How to tackle Slow INSERT for large amount of data in Entity Framework

hi,

i'm using this code to update 10,000+ rows in entity framework. But it's taking more than 1 hour to compete transaction. Why it's taking too much time? Is there any solution of it?

     foreach (Property item in listProperties)
                    {
                        db.Properties.Attach(item);
                        db.Entry(item).Property(x => x.pState).IsModified = true;
                    }
                    db.SaveChanges();