Memory Leak using StreamReader and XmlSerializer

Question

I've been googling for the past few hours and trying different things but can't seem to the bottom of this....

When I run this code, the memory usage continuously grows.

while (true) {     try     {         foreach (string sym in stringlist)         {             StreamReader r = new StreamReader(@"C:\Program Files\" + sym + ".xml");             XmlSerializer xml = new XmlSerializer(typeof(XMLObj), new XmlRootAttribute("rootNode"));             XMLObj obj = (XMLObj)xml.Deserialize(r);                                    obj.Dispose();             r.Dispose();             r.Close();         }     }         catch(Exception ex)      {         Console.WriteLine(ex.ToString());      }     Thread.Sleep(1000);     Console.Clear(); } 

XMLObj is a custom object

[Serializable()] public class XMLObj: IDisposable {     [XmlElement("block")]     public List<XMLnode> nodes{ get; set; }      public XMLObj() { }      public void Dispose()     {         nodes.ForEach(n => n.Dispose());         nodes= null;          GC.SuppressFinalize(this);     } } 

I've tried adding in GC.Collect(); but that doesn't seem to do anything.

Answer 1

The leak is here:

new XmlSerializer(typeof(XMLObj), new XmlRootAttribute("rootNode")) 

XmlSerializer uses assembly generation, and assemblies cannot be collected. It does some automatic cache/reuse for the simplest constructor scenarios (new XmlSerializer(Type), etc), but not for this scenario. Consequently, you should cache it manually:

static readonly XmlSerializer mySerializer =     new XmlSerializer(typeof(XMLObj), new XmlRootAttribute("rootNode")) 

and use the cached serializer instance.