I currently have a game that takes in large images, easily bigger than 1MB, to serve as backgrounds. I know exactly when this transition is supposed to take place, so I made a loader class to handle loading these large images in the background, but when I load the images it still freezes the main thread where the drawing takes place. Since this code runs on the 360 I move the thread to the 4th hardware thread, but that doesn't seem to help. Below is the class I am using. Any thoughts as to why my new content manager which should be in its own thread is interrupting the draw in my main thread would be appreciated.

namespace FileSystem  
{
/// <summary>
/// This is used to reference how many objects reference this texture.
/// Everytime someone references a texture we increase the iNumberOfReferences.
/// When a class calls remove on a specific texture we check to see if anything
/// else is referencing the class, if it is we don't remove it. If there isn't 
/// anything referencing the texture its safe to dispose of.
/// </summary>
class TextureContainer
{
    public uint uiNumberOfReferences = 0;
    public Texture2D texture;
}

/// <summary>
/// This class loads all the files from the Content.
/// </summary>
static class FileManager
{
    static Microsoft.Xna.Framework.Content.ContentManager Content; 
    static EventWaitHandle wh = new AutoResetEvent(false);
    static Dictionary<string, TextureContainer> Texture2DResourceDictionary;
    static List<Texture2D> TexturesToDispose;
    static List<String> TexturesToLoad;
    static int iProcessor = 4;

    private static object threadMutex = new object();
    private static object Texture2DMutex = new object();
    private static object loadingMutex = new object();

    private static bool bLoadingTextures = false;

    /// <summary>
    /// Returns if we are loading textures or not.
    /// </summary>
    public static bool LoadingTexture
    {
        get {
                lock (loadingMutex)
                {
                    return bLoadingTextures;
                }
            }
    }

    /// <summary>
    /// Since this is an static class. This is the constructor for the file loadeder. This is the version
    /// for the Xbox 360.
    /// </summary>
    /// <param name="_Content"></param>
    public static void Initalize(IServiceProvider serviceProvider, string rootDirectory, int _iProcessor )
    {
        Content = new Microsoft.Xna.Framework.Content.ContentManager(serviceProvider, rootDirectory);
        Texture2DResourceDictionary = new Dictionary<string, TextureContainer>();
        TexturesToDispose = new List<Texture2D>();
        iProcessor = _iProcessor;
        CreateThread();
    }

    /// <summary>
    /// Since this is an static class. This is the constructor for the file loadeder.
    /// </summary>
    /// <param name="_Content"></param>
    public static void Initalize(IServiceProvider serviceProvider, string rootDirectory)
    {
        Content = new Microsoft.Xna.Framework.Content.ContentManager(serviceProvider, rootDirectory);
        Texture2DResourceDictionary = new Dictionary<string, TextureContainer>();
        TexturesToDispose = new List<Texture2D>();
        CreateThread();
    }

    /// <summary>
    /// Creates the thread incase we wanted to set up some parameters
    /// Outside of the constructor.
    /// </summary>
    static public void CreateThread()
    {
        Thread t = new Thread(new ThreadStart(StartThread));
        t.Start();

    }

    // This is the function that we thread.
    static public void StartThread()
    {
        //BBSThreadClass BBSTC = (BBSThreadClass)_oData;
        FileManager.Execute();
    }

    /// <summary>
    /// This thread shouldn't be called by the outside world.
    /// It allows the File Manager to loop.
    /// </summary>
    static private void Execute()
    {
        // Make sure our thread is on the correct processor on the XBox 360.
#if WINDOWS 
#else
        Thread.CurrentThread.SetProcessorAffinity(new int[] { iProcessor });
        Thread.CurrentThread.IsBackground = true;
#endif
        // This loop will load textures into ram for us away from the main thread.
        while (true)
        {
            wh.WaitOne();
            // Locking down our data while we process it.
            lock (threadMutex)
            {
                lock (loadingMutex)
                {
                    bLoadingTextures = true;
                }
                bool bContainsKey = false;
                for (int con = 0; con < TexturesToLoad.Count; con++)
                {
                    // If we have already loaded the texture into memory reference
                    // the one in the dictionary.
                    lock (Texture2DMutex)
                    {
                        bContainsKey = Texture2DResourceDictionary.ContainsKey(TexturesToLoad[con]);
                    }

                    if (bContainsKey)
                    {
                        // Do nothing
                    }
                    // Otherwise load it into the dictionary and then reference the
                    // copy in the dictionary
                    else
                    {
                        TextureContainer TC = new TextureContainer();
                        TC.uiNumberOfReferences = 1;    // We start out with 1 referece.
                        // Loading the texture into memory.

                        try
                        {
                            TC.texture = Content.Load<Texture2D>(TexturesToLoad[con]);

                            // This is passed into the dictionary, thus there is only one copy of
                            // the texture in memory.

                            // There is an issue with Sprite Batch and disposing textures.
                            // This will have to wait until its figured out.
                            lock (Texture2DMutex)
                            {
                                bContainsKey = Texture2DResourceDictionary.ContainsKey(TexturesToLoad[con]);
                                Texture2DResourceDictionary.Add(TexturesToLoad[con], TC);
                            }
                            // We don't have the find the reference to the container since we
                            // already have it.
                        }
                        // Occasionally our texture will already by loaded by another thread while 
                        // this thread is operating. This mainly happens on the first level.
                        catch (Exception e)
                        {
                            // If this happens we don't worry about it since this thread only loads
                            // texture data and if its already there we don't need to load it.
                        }
                    }
                    Thread.Sleep(100);
                }
            }
            lock (loadingMutex)
            {
                bLoadingTextures = false;
            }
        }
    }

    static public void LoadTextureList(List<string> _textureList)
    {
        // Ensuring that we can't creating threading problems.
        lock (threadMutex)
        {
            TexturesToLoad = _textureList;
        }
        wh.Set();
    }

    /// <summary>
    /// This loads a 2D texture which represents a 2D grid of Texels.
    /// </summary>
    /// <param name="_textureName">The name of the picture you wish to load.</param>
    /// <returns>Holds the image data.</returns>
    public static Texture2D LoadTexture2D( string _textureName )
    {
        TextureContainer temp;
        lock (Texture2DMutex)
        {
            bool bContainsKey = false;
            // If we have already loaded the texture into memory reference
            // the one in the dictionary.
            lock (Texture2DMutex)
            {
                bContainsKey = Texture2DResourceDictionary.ContainsKey(_textureName);

                if (bContainsKey)
                {
                    temp = Texture2DResourceDictionary[_textureName];
                    temp.uiNumberOfReferences++;    // Incrementing the number of references
                }
                // Otherwise load it into the dictionary and then reference the
                // copy in the dictionary
                else
                {
                    TextureContainer TC = new TextureContainer();
                    TC.uiNumberOfReferences = 1;    // We start out with 1 referece.
                    // Loading the texture into memory.
                    try
                    {
                        TC.texture = Content.Load<Texture2D>(_textureName);

                        // This is passed into the dictionary, thus there is only one copy of
                        // the texture in memory.
                    }
                    // Occasionally our texture will already by loaded by another thread while 
                    // this thread is operating. This mainly happens on the first level.
                    catch(Exception e)
                    {
                        temp = Texture2DResourceDictionary[_textureName];
                        temp.uiNumberOfReferences++;    // Incrementing the number of references
                    }

                    // There is an issue with Sprite Batch and disposing textures.
                    // This will have to wait until its figured out.
                    Texture2DResourceDictionary.Add(_textureName, TC);

                    // We don't have the find the reference to the container since we
                    // already have it.
                    temp = TC;
                }
            }
        }
        // Return a reference to the texture
        return temp.texture;
    }

    /// <summary>
    /// Go through our dictionary and remove any references to the
    /// texture passed in.
    /// </summary>
    /// <param name="texture">Texture to remove from texture dictionary.</param>
    public static void RemoveTexture2D(Texture2D texture)
    {
        foreach (KeyValuePair<string, TextureContainer> pair in Texture2DResourceDictionary)
        {
            // Do our references match?
            if (pair.Value.texture == texture)
            {
                // Only one object or less holds a reference to the 
                // texture. Logically it should be safe to remove.
                if (pair.Value.uiNumberOfReferences <= 1)
                {
                    // Grabing referenc to texture
                    TexturesToDispose.Add(pair.Value.texture);
                    // We are about to release the memory of the texture,
                    // thus we make sure no one else can call this member
                    // in the dictionary.
                    Texture2DResourceDictionary.Remove(pair.Key);
                    // Once we have removed the texture we don't want to create an exception.
                    // So we will stop looking in the list since it has changed.
                    break;
                }
                // More than one Object has a reference to this texture.
                // So we will not be removing it from memory and instead 
                // simply marking down the number of references by 1.
                else
                {
                    pair.Value.uiNumberOfReferences--;
                }
            }
        }
    }

    /*public static void DisposeTextures()
    {
        int Count = TexturesToDispose.Count;
        // If there are any textures to dispose of.
        if (Count > 0)
        {
            for (int con = 0; con < TexturesToDispose.Count; con++)
            {
                // =!THIS REMOVES THE TEXTURE FROM MEMORY!=
                // This is not like a normal dispose. This will actually
                // remove the object from memory. Texture2D is inherited
                // from GraphicsResource which removes it self from 
                // memory on dispose. Very nice for game efficency,
                // but "dangerous" in managed land.
                Texture2D Temp = TexturesToDispose[con];
                Temp.Dispose();
            }
            // Remove textures we've already disposed of.
            TexturesToDispose.Clear();
        }
    }*/

    /// <summary>
    /// This loads a 2D texture which represnets a font.
    /// </summary>
    /// <param name="_textureName">The name of the font you wish to load.</param>
    /// <returns>Holds the font data.</returns>
    public static SpriteFont LoadFont( string _fontName )
    {
        SpriteFont temp = Content.Load<SpriteFont>( _fontName );
        return temp;
    }

    /// <summary>
    /// This loads an XML document.
    /// </summary>
    /// <param name="_textureName">The name of the XML document you wish to load.</param>
    /// <returns>Holds the XML data.</returns>
    public static XmlDocument LoadXML( string _fileName )
    {
        XmlDocument temp = Content.Load<XmlDocument>( _fileName );
        return temp;
    }

    /// <summary>
    /// This loads a sound file.
    /// </summary>
    /// <param name="_fileName"></param>
    /// <returns></returns>
    public static SoundEffect LoadSound( string _fileName )
    {
        SoundEffect temp = Content.Load<SoundEffect>(_fileName);
        return temp;
    }
}
}