--- old/share/memory/virtualspace.cpp	2018-06-14 13:09:53.860858446 -0700
+++ new/share/memory/virtualspace.cpp	2018-06-14 13:09:53.828858445 -0700
@@ -213,7 +213,7 @@
   _size = size;
   _alignment = alignment;
   // If heap is reserved with a backing file, the entire space has been committed. So set the _special flag to true
-  if (_fd_for_heap != -1) {
+  if (_fd_for_heap != -1 && AllocateOldGenAt == NULL) {
     _special = true;
   }
 }
@@ -321,7 +321,6 @@
       Universe::set_narrow_oop_use_implicit_null_checks(false);
     }
   }
-
   _base += _noaccess_prefix;
   _size -= _noaccess_prefix;
   assert(((uintptr_t)_base % _alignment == 0), "must be exactly of required alignment");
@@ -403,7 +402,7 @@
   _alignment = alignment;
 
   // If heap is reserved with a backing file, the entire space has been committed. So set the _special flag to true
-  if (_fd_for_heap != -1) {
+  if (_fd_for_heap != -1 && AllocateOldGenAt == NULL) {
     _special = true;
   }
 
@@ -607,6 +606,24 @@
     return;
   }
 
+  // Open AllocateOldGenAt file
+  if (AllocateOldGenAt != NULL) {
+    _fd_for_heap = os::create_file_for_heap(AllocateOldGenAt);
+    if (_fd_for_heap== -1) {
+      vm_exit_during_initialization(
+        err_msg("Could not create file for Heap at location %s", AllocateOldGenAt));
+    }
+    if (UseParallelOldGC) {
+      // For ParallelOldGC, adaptive sizing picks _old_gen virtual space sizes as needed.
+      // allocate Xmx on NVDIMM as adaptive sizing may put lot of pressure on NVDIMM.
+      os::allocate_file(_fd_for_heap, MaxHeapSize);
+      os::set_nvdimm_fd(_fd_for_heap);
+      os::set_nvdimm_present(true);
+    }
+  } else {
+    _fd_for_heap = -1;
+  }
+
   if (heap_allocation_directory != NULL) {
     _fd_for_heap = os::create_file_for_heap(heap_allocation_directory);
     if (_fd_for_heap == -1) {
@@ -637,9 +654,14 @@
 
   if (base() != NULL) {
     MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap);
+    if (AllocateOldGenAt != NULL && _fd_for_heap != -1) {
+      os::set_nvdimm_present(true);
+      os::set_nvdimm_heapbase((address)_base);
+      os::set_nvdimm_fd(_fd_for_heap);
+    }
   }
 
-  if (_fd_for_heap != -1) {
+  if (_fd_for_heap != -1 && AllocateOldGenAt == NULL) {
     os::close(_fd_for_heap);
   }
 }