--- /dev/null	2018-11-21 22:50:30.000000000 -0800
+++ new/src/hotspot/share/gc/parallel/psFileBackedVirtualspace.cpp	2018-11-21 22:50:29.276788600 -0800
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/parallel/psFileBackedVirtualspace.hpp"
+#include "memory/virtualspace.hpp"
+#include "runtime/os.hpp"
+
+PSFileBackedVirtualSpace::PSFileBackedVirtualSpace(ReservedSpace rs, size_t alignment, const char* path) : PSVirtualSpace(rs, alignment),
+                                                   _file_path(path), _fd(-1), _mapping_succeeded(false) {
+  assert(!rs.special(), "ReservedSpace passed to PSFileBackedVirtualSpace cannot be special");
+}
+
+bool PSFileBackedVirtualSpace::initialize() {
+  _fd = os::create_file_for_heap(_file_path);
+  if (_fd == -1) {
+    return false;
+  }
+  // We map the reserved space to a file at initialization.
+  char* ret = os::replace_existing_mapping_with_file_mapping(reserved_low_addr(), reserved_size(), _fd);
+  if (ret != reserved_low_addr()) {
+    return false;
+  }
+  // _mapping_succeeded is false if we return before this point.
+  // expand calls later check value of this flag and return error if it is false.
+  _mapping_succeeded = true;
+  _special = true;
+  return true;
+}
+
+PSFileBackedVirtualSpace::PSFileBackedVirtualSpace(ReservedSpace rs, const char* path) {
+  PSFileBackedVirtualSpace(rs, os::vm_page_size(), path);
+}
+
+bool PSFileBackedVirtualSpace::expand_by(size_t bytes) {
+  assert(special(), "Since entire space is committed at initialization, _special should always be true for PSFileBackedVirtualSpace");
+
+  // if mapping did not succeed during intialization return false
+  if (!_mapping_succeeded) {
+    return false;
+  }
+  return PSVirtualSpace::expand_by(bytes);
+
+}
+
+bool PSFileBackedVirtualSpace::shrink_by(size_t bytes) {
+  assert(special(), "Since entire space is committed at initialization, _special should always be true for PSFileBackedVirtualSpace");
+  return PSVirtualSpace::shrink_by(bytes);
+}
+
+size_t PSFileBackedVirtualSpace::expand_into(PSVirtualSpace* space, size_t bytes) {
+  // not supported. Since doing this will change page mapping which will lead to large TLB penalties.
+  assert(false, "expand_into() should not be called for PSFileBackedVirtualSpace");
+  return 0;
+}
+
+void PSFileBackedVirtualSpace::release() {
+  os::close(_fd);
+  _fd = -1;
+  _file_path = NULL;
+
+  PSVirtualSpace::release();
+}
+