AssetBundle and memory leaks

Unity Engine
,
1

Hi all.
Currently, for a small game with very special font, I choose to show them as Textures.
So to manage multi language, I create one asset bundle for each language.
To load an Asset bundle, I do this :

private IEnumerator SetLanguage(string currentLanguage)
{
	if (currentDownload == null)
	{
		PlayerPrefs.SetString("Language", currentLanguage);
		string downloadDataPath;
		if (Application.isEditor)
		{
			downloadDataPath = Application.dataPath + "/StreamingAssets/";
		}
		else
		{
   			downloadDataPath = Application.dataPath + "/Raw/";
		}
           if (Screen.width < 500)
           {
		    currentDownload = new WWW ("file://" + downloadDataPath + currentLanguage + "Language.unity3d");
           }
           else
           {
               currentDownload = new WWW ("file://" + downloadDataPath + currentLanguage + "HDLanguage.unity3d");
           }
		isDownloading = true;
		return;
	}
	else
	{
		if (oldAssetBundle != null)
		{
			oldAssetBundle.Unload(true);
		}
		AssetBundle currentAssetBundle = currentDownload.assetBundle;
		buttons = currentAssetBundle.Load("buttons") as Texture2D;
		menus = currentAssetBundle.Load("mainmenu") as Texture2D;
		messages = currentAssetBundle.Load("hudmsg") as Texture2D;
                help = currentAssetBundle.Load("help") as Texture2D;
		touchScreenRenderer.material.SetTexture("_MainTex", buttons);
		buttonPlayRenderer.material.SetTexture("_MainTex", menus);
		buttonHelpRenderer.material.SetTexture("_MainTex", menus);
       	        buttonOptionsRenderer.material.SetTexture("_MainTex", menus);
       	        buttonCreditsRenderer.material.SetTexture("_MainTex", menus);
       	        buttonMusicRenderer.material.SetTexture("_MainTex", menus);
       	        buttonFXRenderer.material.SetTexture("_MainTex", menus);
         	buttonLanguagesRenderer.material.SetTexture("_MainTex", menus);
        	selectLanguageRenderer.material.SetTexture("_MainTex", messages);
		Vector2 temp = selectLanguageRenderer.material.mainTextureOffset;
		temp.y = 0.5f;
		selectLanguageRenderer.material.mainTextureOffset = temp;
        	Renderer titleRenderer = title.GetComponentInChildren<Renderer>() as Renderer;
        	titleRenderer.material.SetTexture("_MainTex", menus);
                helpText01.renderer.material.SetTexture("_MainTex", help);
                helpText02.renderer.material.SetTexture("_MainTex", help);
        	oldAssetBundle = currentAssetBundle;
        	currentDownload.Dispose();
        	currentDownload = null;
        	isDownloading = false;
        	if (oldAssetBundle != null)
		{
			oldAssetBundle.Unload(false);
		}
	}
}

As you can see I think I correctly free all memory but if I change language many times, It always finish by a crash.
More the iphone is recent, most I need to change language, so it’s really a memory problem.
But I can’t see what i’ve done wrong.
Could you help me please?
PS/ when I do this on the editor, my computer lag a lot, all memory must be used but if I show memory usage in the editor, nothing wrong and there is no sign of a memory leak.

2

what timeframe does “many times” happen in?
unloading does not happen immediately, so if you try to switch 20 times per second you will indeed get into trouble

3

I only load a new one when a previous one have finish to load successfully. To load an asset bundle it take 1 or 2 second. But to test it I change language immediately so I think it’s sommething like 1 each 1 or 2 seconds. So how many time did it take to unload everything. Is there a way to force an immediate unloading?
And is there a way to know that everything is correctly unloaded?

4

“immediate unloading” is what you request there but immediate still does not mean “here now this moment” cause it will not be issued until at very least the end of the frame. the world can’t just break appart in the middle of the frame .)

5

hum, I made some test, but even by waiting some frame (like 100) between unload and new load, there is always the same problem :s
Something must persist in memory, or I gorget something to unload in my function above.

6

perhaps you forgot to kill the objects that use the material prior to unloading the bundle or so

7

hum I don’t know, As you can see, my assetBundle contain only texture. The only thing I do is change thus texture at each loading. So I don’t think I need to kill my objects that use the material.
With my previous test, AssetBundle.Unload(true) correctly delete my texture, all material become white after this. So they are correctly unloaded.