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diff --git a/src/rocksdb/include/rocksdb/thread_status.h b/src/rocksdb/include/rocksdb/thread_status.h
new file mode 100644
index 000000000..1b5f8c046
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+++ b/src/rocksdb/include/rocksdb/thread_status.h
@@ -0,0 +1,189 @@
+// 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).
+//
+// This file defines the structures for exposing run-time status of any
+// rocksdb-related thread.  Such run-time status can be obtained via
+// GetThreadList() API.
+//
+// Note that all thread-status features are still under-development, and
+// thus APIs and class definitions might subject to change at this point.
+// Will remove this comment once the APIs have been finalized.
+
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <map>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "rocksdb/rocksdb_namespace.h"
+
+#if !defined(ROCKSDB_LITE) && !defined(NROCKSDB_THREAD_STATUS)
+#define ROCKSDB_USING_THREAD_STATUS
+#endif
+
+namespace ROCKSDB_NAMESPACE {
+
+// TODO(yhchiang): remove this function once c++14 is available
+//                 as std::max will be able to cover this.
+// Current MS compiler does not support constexpr
+template <int A, int B>
+struct constexpr_max {
+  static const int result = (A > B) ? A : B;
+};
+
+// A structure that describes the current status of a thread.
+// The status of active threads can be fetched using
+// ROCKSDB_NAMESPACE::GetThreadList().
+struct ThreadStatus {
+  // The type of a thread.
+  enum ThreadType : int {
+    HIGH_PRIORITY = 0,  // RocksDB BG thread in high-pri thread pool
+    LOW_PRIORITY,       // RocksDB BG thread in low-pri thread pool
+    USER,               // User thread (Non-RocksDB BG thread)
+    BOTTOM_PRIORITY,    // RocksDB BG thread in bottom-pri thread pool
+    NUM_THREAD_TYPES
+  };
+
+  // The type used to refer to a thread operation.
+  // A thread operation describes high-level action of a thread.
+  // Examples include compaction and flush.
+  enum OperationType : int {
+    OP_UNKNOWN = 0,
+    OP_COMPACTION,
+    OP_FLUSH,
+    NUM_OP_TYPES
+  };
+
+  enum OperationStage : int {
+    STAGE_UNKNOWN = 0,
+    STAGE_FLUSH_RUN,
+    STAGE_FLUSH_WRITE_L0,
+    STAGE_COMPACTION_PREPARE,
+    STAGE_COMPACTION_RUN,
+    STAGE_COMPACTION_PROCESS_KV,
+    STAGE_COMPACTION_INSTALL,
+    STAGE_COMPACTION_SYNC_FILE,
+    STAGE_PICK_MEMTABLES_TO_FLUSH,
+    STAGE_MEMTABLE_ROLLBACK,
+    STAGE_MEMTABLE_INSTALL_FLUSH_RESULTS,
+    NUM_OP_STAGES
+  };
+
+  enum CompactionPropertyType : int {
+    COMPACTION_JOB_ID = 0,
+    COMPACTION_INPUT_OUTPUT_LEVEL,
+    COMPACTION_PROP_FLAGS,
+    COMPACTION_TOTAL_INPUT_BYTES,
+    COMPACTION_BYTES_READ,
+    COMPACTION_BYTES_WRITTEN,
+    NUM_COMPACTION_PROPERTIES
+  };
+
+  enum FlushPropertyType : int {
+    FLUSH_JOB_ID = 0,
+    FLUSH_BYTES_MEMTABLES,
+    FLUSH_BYTES_WRITTEN,
+    NUM_FLUSH_PROPERTIES
+  };
+
+  // The maximum number of properties of an operation.
+  // This number should be set to the biggest NUM_XXX_PROPERTIES.
+  static const int kNumOperationProperties =
+      constexpr_max<NUM_COMPACTION_PROPERTIES, NUM_FLUSH_PROPERTIES>::result;
+
+  // The type used to refer to a thread state.
+  // A state describes lower-level action of a thread
+  // such as reading / writing a file or waiting for a mutex.
+  enum StateType : int {
+    STATE_UNKNOWN = 0,
+    STATE_MUTEX_WAIT = 1,
+    NUM_STATE_TYPES
+  };
+
+  ThreadStatus(const uint64_t _id, const ThreadType _thread_type,
+               const std::string& _db_name, const std::string& _cf_name,
+               const OperationType _operation_type,
+               const uint64_t _op_elapsed_micros,
+               const OperationStage _operation_stage,
+               const uint64_t _op_props[], const StateType _state_type)
+      : thread_id(_id),
+        thread_type(_thread_type),
+        db_name(_db_name),
+        cf_name(_cf_name),
+        operation_type(_operation_type),
+        op_elapsed_micros(_op_elapsed_micros),
+        operation_stage(_operation_stage),
+        state_type(_state_type) {
+    for (int i = 0; i < kNumOperationProperties; ++i) {
+      op_properties[i] = _op_props[i];
+    }
+  }
+
+  // An unique ID for the thread.
+  const uint64_t thread_id;
+
+  // The type of the thread, it could be HIGH_PRIORITY,
+  // LOW_PRIORITY, and USER
+  const ThreadType thread_type;
+
+  // The name of the DB instance where the thread is currently
+  // involved with.  It would be set to empty string if the thread
+  // does not involve in any DB operation.
+  const std::string db_name;
+
+  // The name of the column family where the thread is currently
+  // It would be set to empty string if the thread does not involve
+  // in any column family.
+  const std::string cf_name;
+
+  // The operation (high-level action) that the current thread is involved.
+  const OperationType operation_type;
+
+  // The elapsed time of the current thread operation in microseconds.
+  const uint64_t op_elapsed_micros;
+
+  // An integer showing the current stage where the thread is involved
+  // in the current operation.
+  const OperationStage operation_stage;
+
+  // A list of properties that describe some details about the current
+  // operation.  Same field in op_properties[] might have different
+  // meanings for different operations.
+  uint64_t op_properties[kNumOperationProperties];
+
+  // The state (lower-level action) that the current thread is involved.
+  const StateType state_type;
+
+  // The followings are a set of utility functions for interpreting
+  // the information of ThreadStatus
+
+  static std::string GetThreadTypeName(ThreadType thread_type);
+
+  // Obtain the name of an operation given its type.
+  static const std::string& GetOperationName(OperationType op_type);
+
+  static const std::string MicrosToString(uint64_t op_elapsed_time);
+
+  // Obtain a human-readable string describing the specified operation stage.
+  static const std::string& GetOperationStageName(OperationStage stage);
+
+  // Obtain the name of the "i"th operation property of the
+  // specified operation.
+  static const std::string& GetOperationPropertyName(OperationType op_type,
+                                                     int i);
+
+  // Translate the "i"th property of the specified operation given
+  // a property value.
+  static std::map<std::string, uint64_t> InterpretOperationProperties(
+      OperationType op_type, const uint64_t* op_properties);
+
+  // Obtain the name of a state given its type.
+  static const std::string& GetStateName(StateType state_type);
+};
+
+}  // namespace ROCKSDB_NAMESPACE