Making the J2KDecoderModule decoder function async. Could this be the cause of sim freeze? -- HandleRequestImage in LLClientView is now sync, which means that it cannot take too long to complete. However, its execution path may end up in J2KDecoderModule.Decode, which is heavy and could stop the packet processing thread while it's at it.

OpenSim/Region/CoreModules/Agent/TextureSender/J2KDecoderModule.cs

@@ -166,7 +166,7 @@ namespace OpenSim.Region.CoreModules.Agent.TextureSender
 
                 // Do Decode!
                 if (decode)
-                    Decode(assetID, j2kData);
+                    Util.FireAndForget(delegate { Decode(assetID, j2kData); });
             }
         }