diff -r c70ebf41026a -r 27ae9bbef86a src/share/vm/runtime/os.hpp
--- a/src/share/vm/runtime/os.hpp	Fri Dec 02 11:07:27 2016 +0100
+++ b/src/share/vm/runtime/os.hpp	Thu Dec 15 19:48:32 2016 -0500
@@ -151,6 +151,7 @@
 
   static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned);
 
+  static void initialize_initial_active_processor_count();
  public:
   static void init(void);                      // Called before command line parsing
   static void init_before_ergo(void);          // Called after command line parsing
@@ -238,6 +239,13 @@
   // Note that on some OSes this can change dynamically.
   static int active_processor_count();
 
+  // At startup the number of active CPUs this process is allowed to run on.
+  // This value does not change dynamically. May be different from active_processor_count().
+  static int initial_active_processor_count() {
+    assert(_initial_active_processor_count > 0, "Initial active processor count not set yet.");
+    return _initial_active_processor_count;
+  }
+
   // Bind processes to processors.
   //     This is a two step procedure:
   //     first you generate a distribution of processes to processors,
@@ -975,8 +983,9 @@
 
 
  protected:
-  static long _rand_seed;                   // seed for random number generator
-  static int _processor_count;              // number of processors
+  static long _rand_seed;                     // seed for random number generator
+  static int _processor_count;                // number of processors
+  static int _initial_active_processor_count; // number of active processors during initialization.
 
   static char* format_boot_path(const char* format_string,
                                 const char* home,