XmlSerializer: Deserialize Perfomance Issue

Deserializing large xml files (>500kb) can be quite slow, because it produces a lot of harddrive IO operations. There is a simple  trick to avoid this using a memory stream:

UTF8Encoding encoding = new UTF8Encoding();
XmlSerializer serializer = new XmlSerializer(typeof(MyClass));
MemoryStream stream =
      new MemoryStream(encoding.GetBytes(File.ReadAllText(filename)));
MyClass myClass = (MyClass)serializer.Deserialize(stream);