--- /dev/null	2013-11-01 16:26:05.000000000 +0100
+++ new/src/share/vm/gc_implementation/parallelScavenge/generationSizer.cpp	2013-11-01 16:26:05.000000000 +0100
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2001, 2013, 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_implementation/parallelScavenge/generationSizer.hpp"
+#include "memory/collectorPolicy.hpp"
+
+void GenerationSizer::trace_gen_sizes(const char* const str) {
+  if (TracePageSizes) {
+    tty->print_cr("%s:  " SIZE_FORMAT "," SIZE_FORMAT " "
+                  SIZE_FORMAT "," SIZE_FORMAT " "
+                  SIZE_FORMAT,
+                  str,
+                  _min_gen1_size / K, _max_gen1_size / K,
+                  _min_gen0_size / K, _max_gen0_size / K,
+                  _max_heap_byte_size / K);
+  }
+}
+
+void GenerationSizer::initialize_alignments() {
+  _space_alignment = _gen_alignment = default_gen_alignment();
+  _heap_alignment = compute_heap_alignment();
+}
+
+void GenerationSizer::initialize_flags() {
+  // Do basic sizing work
+  TwoGenerationCollectorPolicy::initialize_flags();
+
+  assert(UseSerialGC ||
+          !FLAG_IS_DEFAULT(ParallelGCThreads) ||
+          (ParallelGCThreads > 0),
+         "ParallelGCThreads should be set before flag initialization");
+
+  // The survivor ratio's are calculated "raw", unlike the
+  // default gc, which adds 2 to the ratio value. We need to
+  // make sure the values are valid before using them.
+  if (MinSurvivorRatio < 3) {
+    FLAG_SET_ERGO(uintx, MinSurvivorRatio, 3);
+  }
+
+  if (InitialSurvivorRatio < 3) {
+    FLAG_SET_ERGO(uintx, InitialSurvivorRatio, 3);
+  }
+}
+
+void GenerationSizer::initialize_size_info() {
+  trace_gen_sizes("ps heap raw");
+  const size_t page_sz = os::page_size_for_region(_min_heap_byte_size,
+                                                  _max_heap_byte_size,
+                                                  8);
+
+  // Can a page size be something else than a power of two?
+  assert(is_power_of_2((intptr_t)page_sz), "must be a power of 2");
+  size_t new_alignment = round_to(page_sz, _gen_alignment);
+  if (new_alignment != _gen_alignment) {
+    _gen_alignment = new_alignment;
+    // Redo everything from the start
+    initialize_flags();
+  }
+  TwoGenerationCollectorPolicy::initialize_size_info();
+
+  trace_gen_sizes("ps heap rnd");
+}