--- /dev/null	2020-05-05 16:06:32.280000000 +0000
+++ new/src/hotspot/share/gc/g1/g1OldGenAllocationTracker.hpp	2020-06-04 15:48:30.715489745 +0000
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2020, Amazon.com, Inc. 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.
+ *
+ */
+
+#ifndef SHARE_VM_GC_G1_G1OLDGENALLOCATIONTRACKER_HPP
+#define SHARE_VM_GC_G1_G1OLDGENALLOCATIONTRACKER_HPP
+
+#include "gc/g1/heapRegion.hpp"
+#include "memory/allocation.hpp"
+
+// Track allocation details in the old generation.
+class G1OldGenAllocationTracker : public CHeapObj<mtGC> {
+  // New bytes allocated in old gen between the end of the last GC and
+  // the end of the GC before that.
+  size_t _last_cycle_old_bytes;
+  // The number of seconds between the end of the last GC and
+  // the end of the GC before that.
+  double _last_cycle_duration;
+
+  size_t _allocated_bytes_since_last_gc;
+
+  void reset_cycle_after_gc() {
+    _last_cycle_old_bytes = _allocated_bytes_since_last_gc;
+    _allocated_bytes_since_last_gc = 0;
+  }
+
+public:
+  G1OldGenAllocationTracker();
+  // Add the given number of bytes to the total number of allocated bytes in the old gen.
+  void add_allocated_bytes_since_last_gc(size_t bytes) { _allocated_bytes_since_last_gc += bytes; }
+
+  size_t last_cycle_old_bytes() { return _last_cycle_old_bytes; }
+
+  double last_cycle_duration() { return _last_cycle_duration; }
+
+  // Reset stats after a collection.
+  void reset_after_full_gc();
+  void reset_after_young_gc(double allocation_duration_s);
+};
+
+#endif // SHARE_VM_GC_G1_G1OLDGENALLOCATIONTRACKER_HPP
\ No newline at end of file