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diff --git a/storage/rocksdb/atomic_stat.h b/storage/rocksdb/atomic_stat.h
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+/* This is an atomic integer abstract data type, for high-performance
+   tracking of a single stat.  It intentionally permits inconsistent
+   atomic operations and reads, for better performance.  This means
+   that, though no data should ever be lost by this stat, reads of it
+   at any time may not include all changes up to any particular point.
+
+   So, values read from these may only be approximately correct.
+
+   If your use-case will fail under these conditions, do not use this.
+
+   Copyright (C) 2012 - 2014 Steaphan Greene <steaphan@gmail.com>
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; either version 2
+   of the License, or (at your option) any later version.
+
+   This program 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 for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the
+   Free Software Foundation, Inc.
+   51 Franklin Street, Fifth Floor
+   Boston, MA  02110-1301, USA.
+*/
+
+#ifndef _atomic_stat_h_
+#define _atomic_stat_h_
+
+#include <atomic>
+
+template < typename TYPE >
+class atomic_stat {
+public:
+  // Initialize value to the default for the type
+  atomic_stat() : value_(TYPE()) {};
+
+  // This enforces a strict order, as all absolute sets should
+  void clear() {
+    value_.store(TYPE(), std::memory_order_seq_cst);
+  };
+
+  // Reads can get any valid value, it doesn't matter which, exactly
+  TYPE load() const {
+    return value_.load(std::memory_order_relaxed);
+  };
+
+  // This only supplies relative arithmetic operations
+  // These are all done atomically, and so can show up in any order
+  void inc(const TYPE &other) {
+    value_.fetch_add(other, std::memory_order_relaxed);
+  };
+
+  void dec(const TYPE &other) {
+    value_.fetch_sub(other, std::memory_order_relaxed);
+  };
+
+  void inc() {
+    value_.fetch_add(1, std::memory_order_relaxed);
+  };
+
+  void dec() {
+    value_.fetch_sub(1, std::memory_order_relaxed);
+  };
+
+  // This will make one attempt to set the value to the max of
+  // the current value, and the passed-in value.  It can fail
+  // for any reason, and we only try it once.
+  void set_max_maybe(const TYPE &new_val) {
+    TYPE old_val = value_;
+    if (new_val > old_val) {
+      value_.compare_exchange_weak(old_val, new_val,
+                                   std::memory_order_relaxed,
+                                   std::memory_order_relaxed);
+    }
+  };
+
+  // This will make one attempt to assign the value to the passed-in
+  // value.  It can fail for any reason, and we only try it once.
+  void set_maybe(const TYPE &new_val) {
+    TYPE old_val = value_;
+    value_.compare_exchange_weak(old_val, new_val,
+                                 std::memory_order_relaxed,
+                                 std::memory_order_relaxed);
+  };
+
+private:
+  std::atomic<TYPE> value_;
+};
+
+#endif // _atomic_stat_h_