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diff --git a/src/rocksdb/monitoring/persistent_stats_history.h b/src/rocksdb/monitoring/persistent_stats_history.h
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+++ b/src/rocksdb/monitoring/persistent_stats_history.h
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+// Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#pragma once
+
+#include "db/db_impl/db_impl.h"
+#include "rocksdb/stats_history.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+extern const std::string kFormatVersionKeyString;
+extern const std::string kCompatibleVersionKeyString;
+extern const uint64_t kStatsCFCurrentFormatVersion;
+extern const uint64_t kStatsCFCompatibleFormatVersion;
+
+enum StatsVersionKeyType : uint32_t {
+  kFormatVersion = 1,
+  kCompatibleVersion = 2,
+  kKeyTypeMax = 3
+};
+
+// Read the version number from persitent stats cf depending on type provided
+// stores the version number in `*version_number`
+// returns Status::OK() on success, or other status code on failure
+Status DecodePersistentStatsVersionNumber(DBImpl* db, StatsVersionKeyType type,
+                                          uint64_t* version_number);
+
+// Encode timestamp and stats key into buf
+// Format: timestamp(10 digit) + '#' + key
+// Total length of encoded key will be capped at 100 bytes
+int EncodePersistentStatsKey(uint64_t timestamp, const std::string& key,
+                             int size, char* buf);
+
+void OptimizeForPersistentStats(ColumnFamilyOptions* cfo);
+
+class PersistentStatsHistoryIterator final : public StatsHistoryIterator {
+ public:
+  PersistentStatsHistoryIterator(uint64_t start_time, uint64_t end_time,
+                                 DBImpl* db_impl)
+      : time_(0),
+        start_time_(start_time),
+        end_time_(end_time),
+        valid_(true),
+        db_impl_(db_impl) {
+    AdvanceIteratorByTime(start_time_, end_time_);
+  }
+  ~PersistentStatsHistoryIterator() override;
+  bool Valid() const override;
+  Status status() const override;
+
+  void Next() override;
+  uint64_t GetStatsTime() const override;
+
+  const std::map<std::string, uint64_t>& GetStatsMap() const override;
+
+ private:
+  // advance the iterator to the next stats history record with timestamp
+  // between [start_time, end_time)
+  void AdvanceIteratorByTime(uint64_t start_time, uint64_t end_time);
+
+  // No copying allowed
+  PersistentStatsHistoryIterator(const PersistentStatsHistoryIterator&) =
+      delete;
+  void operator=(const PersistentStatsHistoryIterator&) = delete;
+  PersistentStatsHistoryIterator(PersistentStatsHistoryIterator&&) = delete;
+  PersistentStatsHistoryIterator& operator=(PersistentStatsHistoryIterator&&) =
+      delete;
+
+  uint64_t time_;
+  uint64_t start_time_;
+  uint64_t end_time_;
+  std::map<std::string, uint64_t> stats_map_;
+  Status status_;
+  bool valid_;
+  DBImpl* db_impl_;
+};
+
+}  // namespace ROCKSDB_NAMESPACE