blob: 93ecb9af7954742bf61a3418cab03dcb65785777 [file] [log] [blame]
// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stddef.h>
#include <stdint.h>
#include "base/containers/circular_deque.h"
#include "base/macros.h"
#include "base/threading/thread_checker.h"
namespace remoting {
// Calculates the maximum or average of the most recent N recorded samples.
// This is typically used to smooth out random variation in point samples
// over bandwidth, frame rate, etc.
class RunningSamples {
// Constructs a running sample helper that stores |window_size| most
// recent samples.
explicit RunningSamples(int window_size);
virtual ~RunningSamples();
// Records a point sample.
void Record(int64_t value);
// Returns the average over up to |window_size| of the most recent samples.
// 0 if no sample available
double Average() const;
// Returns the max over up to |window_size| of the most recent samples.
// 0 if no sample available
int64_t Max() const;
// Whether there is at least one record.
bool IsEmpty() const;
// Stores the desired window size, as size_t to avoid casting when comparing
// with the size of |data_points_|.
const size_t window_size_;
// Stores the |window_size| most recently recorded samples.
base::circular_deque<int64_t> data_points_;
// Holds the sum of the samples in |data_points_|.
int64_t sum_ = 0;
base::ThreadChecker thread_checker_;
} // namespace remoting