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diff --git a/src/rocksdb/include/rocksdb/threadpool.h b/src/rocksdb/include/rocksdb/threadpool.h
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+++ b/src/rocksdb/include/rocksdb/threadpool.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 <functional>
+
+#include "rocksdb/rocksdb_namespace.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+/*
+ * ThreadPool is a component that will spawn N background threads that will
+ * be used to execute scheduled work, The number of background threads could
+ * be modified by calling SetBackgroundThreads().
+ * */
+class ThreadPool {
+ public:
+  virtual ~ThreadPool() {}
+
+  // Wait for all threads to finish.
+  // Discard those threads that did not start
+  // executing
+  virtual void JoinAllThreads() = 0;
+
+  // Set the number of background threads that will be executing the
+  // scheduled jobs.
+  virtual void SetBackgroundThreads(int num) = 0;
+  virtual int GetBackgroundThreads() = 0;
+
+  // Get the number of jobs scheduled in the ThreadPool queue.
+  virtual unsigned int GetQueueLen() const = 0;
+
+  // Waits for all jobs to complete those
+  // that already started running and those that did not
+  // start yet. This ensures that everything that was thrown
+  // on the TP runs even though
+  // we may not have specified enough threads for the amount
+  // of jobs
+  virtual void WaitForJobsAndJoinAllThreads() = 0;
+
+  // Submit a fire and forget jobs
+  // This allows to submit the same job multiple times
+  virtual void SubmitJob(const std::function<void()>&) = 0;
+  // This moves the function in for efficiency
+  virtual void SubmitJob(std::function<void()>&&) = 0;
+
+  // Reserve available background threads. This function does not ensure
+  // so many threads can be reserved, instead it will return the number of
+  // threads that can be reserved against the desired one. In other words,
+  // the number of available threads could be less than the input.
+  virtual int ReserveThreads(int /*threads_to_be_reserved*/) { return 0; }
+
+  // Release a specific number of reserved threads
+  virtual int ReleaseThreads(int /*threads_to_be_released*/) { return 0; }
+};
+
+// NewThreadPool() is a function that could be used to create a ThreadPool
+// with `num_threads` background threads.
+extern ThreadPool* NewThreadPool(int num_threads);
+
+}  // namespace ROCKSDB_NAMESPACE