dotnet-core/release-notes/2.1/Preview/api-diff/preview2/2.1-preview2_System.Threading.md

System.Threading

 namespace System.Threading {
     public sealed class Thread : CriticalFinalizerObject {
+        public static int GetCurrentProcessorId();
     }
     public static class ThreadPool {
-        public static bool QueueUserWorkItem(WaitCallback callBack, object state, bool preferLocal);

+        public static bool QueueUserWorkItem<TState>(Action<TState> callBack, TState state, bool preferLocal);
     }
 }