pineapple/src/core/perf_stats.h
2022-11-05 13:58:44 +01:00

103 lines
3.5 KiB
C++
Executable file

// SPDX-FileCopyrightText: 2017 Citra Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#pragma once
#include <array>
#include <atomic>
#include <chrono>
#include <cstddef>
#include <mutex>
#include "common/common_types.h"
namespace Core {
struct PerfStatsResults {
/// System FPS (LCD VBlanks) in Hz
double system_fps;
/// Average game FPS (GPU frame renders) in Hz
double average_game_fps;
/// Walltime per system frame, in seconds, excluding any waits
double frametime;
/// Ratio of walltime / emulated time elapsed
double emulation_speed;
};
/**
* Class to manage and query performance/timing statistics. All public functions of this class are
* thread-safe unless stated otherwise.
*/
class PerfStats {
public:
explicit PerfStats(u64 title_id_);
~PerfStats();
using Clock = std::chrono::steady_clock;
void BeginSystemFrame();
void EndSystemFrame();
void EndGameFrame();
PerfStatsResults GetAndResetStats(std::chrono::microseconds current_system_time_us);
/**
* Returns the arithmetic mean of all frametime values stored in the performance history.
*/
double GetMeanFrametime() const;
/**
* Gets the ratio between walltime and the emulated time of the previous system frame. This is
* useful for scaling inputs or outputs moving between the two time domains.
*/
double GetLastFrameTimeScale() const;
private:
mutable std::mutex object_mutex;
/// Title ID for the game that is running. 0 if there is no game running yet
u64 title_id{0};
/// Current index for writing to the perf_history array
std::size_t current_index{0};
/// Stores an hour of historical frametime data useful for processing and tracking performance
/// regressions with code changes.
std::array<double, 216000> perf_history{};
/// Point when the cumulative counters were reset
Clock::time_point reset_point = Clock::now();
/// System time when the cumulative counters were reset
std::chrono::microseconds reset_point_system_us{0};
/// Cumulative duration (excluding v-sync/frame-limiting) of frames since last reset
Clock::duration accumulated_frametime = Clock::duration::zero();
/// Cumulative number of system frames (LCD VBlanks) presented since last reset
u32 system_frames = 0;
/// Cumulative number of game frames (GSP frame submissions) since last reset
std::atomic<u32> game_frames = 0;
/// Point when the previous system frame ended
Clock::time_point previous_frame_end = reset_point;
/// Point when the current system frame began
Clock::time_point frame_begin = reset_point;
/// Total visible duration (including frame-limiting, etc.) of the previous system frame
Clock::duration previous_frame_length = Clock::duration::zero();
/// Previously computed fps
double previous_fps = 0;
};
class SpeedLimiter {
public:
using Clock = std::chrono::steady_clock;
void DoSpeedLimiting(std::chrono::microseconds current_system_time_us);
private:
/// Emulated system time (in microseconds) at the last limiter invocation
std::chrono::microseconds previous_system_time_us{0};
/// Walltime at the last limiter invocation
Clock::time_point previous_walltime = Clock::now();
/// Accumulated difference between walltime and emulated time
std::chrono::microseconds speed_limiting_delta_err{0};
};
} // namespace Core