yuzu-android/src/core/perf_stats.cpp
2021-11-03 21:42:57 -04:00

164 lines
5.7 KiB
C++

// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <chrono>
#include <iterator>
#include <mutex>
#include <numeric>
#include <sstream>
#include <thread>
#include <fmt/chrono.h>
#include <fmt/format.h>
#include "common/fs/file.h"
#include "common/fs/fs.h"
#include "common/fs/path_util.h"
#include "common/settings.h"
#include "core/perf_stats.h"
using namespace std::chrono_literals;
using DoubleSecs = std::chrono::duration<double, std::chrono::seconds::period>;
using std::chrono::duration_cast;
using std::chrono::microseconds;
// Purposefully ignore the first five frames, as there's a significant amount of overhead in
// booting that we shouldn't account for
constexpr std::size_t IgnoreFrames = 5;
namespace Core {
PerfStats::PerfStats(u64 title_id_) : title_id(title_id_) {}
PerfStats::~PerfStats() {
if (!Settings::values.record_frame_times || title_id == 0) {
return;
}
const std::time_t t = std::time(nullptr);
std::ostringstream stream;
std::copy(perf_history.begin() + IgnoreFrames, perf_history.begin() + current_index,
std::ostream_iterator<double>(stream, "\n"));
const auto path = Common::FS::GetYuzuPath(Common::FS::YuzuPath::LogDir);
// %F Date format expanded is "%Y-%m-%d"
const auto filename = fmt::format("{:%F-%H-%M}_{:016X}.csv", *std::localtime(&t), title_id);
const auto filepath = path / filename;
if (Common::FS::CreateParentDir(filepath)) {
Common::FS::IOFile file(filepath, Common::FS::FileAccessMode::Write,
Common::FS::FileType::TextFile);
void(file.WriteString(stream.str()));
}
}
void PerfStats::BeginSystemFrame() {
std::lock_guard lock{object_mutex};
frame_begin = Clock::now();
}
void PerfStats::EndSystemFrame() {
std::lock_guard lock{object_mutex};
auto frame_end = Clock::now();
const auto frame_time = frame_end - frame_begin;
if (current_index < perf_history.size()) {
perf_history[current_index++] =
std::chrono::duration<double, std::milli>(frame_time).count();
}
accumulated_frametime += frame_time;
system_frames += 1;
previous_frame_length = frame_end - previous_frame_end;
previous_frame_end = frame_end;
}
void PerfStats::EndGameFrame() {
game_frames.fetch_add(1, std::memory_order_relaxed);
}
double PerfStats::GetMeanFrametime() const {
std::lock_guard lock{object_mutex};
if (current_index <= IgnoreFrames) {
return 0;
}
const double sum = std::accumulate(perf_history.begin() + IgnoreFrames,
perf_history.begin() + current_index, 0.0);
return sum / static_cast<double>(current_index - IgnoreFrames);
}
PerfStatsResults PerfStats::GetAndResetStats(microseconds current_system_time_us) {
std::lock_guard lock{object_mutex};
const auto now = Clock::now();
// Walltime elapsed since stats were reset
const auto interval = duration_cast<DoubleSecs>(now - reset_point).count();
const auto system_us_per_second = (current_system_time_us - reset_point_system_us) / interval;
const auto current_frames = static_cast<double>(game_frames.load(std::memory_order_relaxed));
const auto current_fps = current_frames / interval;
const PerfStatsResults results{
.system_fps = static_cast<double>(system_frames) / interval,
.average_game_fps = (current_fps + previous_fps) / 2.0,
.frametime = duration_cast<DoubleSecs>(accumulated_frametime).count() /
static_cast<double>(system_frames),
.emulation_speed = system_us_per_second.count() / 1'000'000.0,
};
// Reset counters
reset_point = now;
reset_point_system_us = current_system_time_us;
accumulated_frametime = Clock::duration::zero();
system_frames = 0;
game_frames.store(0, std::memory_order_relaxed);
previous_fps = current_fps;
return results;
}
double PerfStats::GetLastFrameTimeScale() const {
std::lock_guard lock{object_mutex};
constexpr double FRAME_LENGTH = 1.0 / 60;
return duration_cast<DoubleSecs>(previous_frame_length).count() / FRAME_LENGTH;
}
void SpeedLimiter::DoSpeedLimiting(microseconds current_system_time_us) {
if (!Settings::values.use_speed_limit.GetValue() ||
Settings::values.use_multi_core.GetValue()) {
return;
}
auto now = Clock::now();
const double sleep_scale = Settings::values.speed_limit.GetValue() / 100.0;
// Max lag caused by slow frames. Shouldn't be more than the length of a frame at the current
// speed percent or it will clamp too much and prevent this from properly limiting to that
// percent. High values means it'll take longer after a slow frame to recover and start
// limiting
const microseconds max_lag_time_us = duration_cast<microseconds>(
std::chrono::duration<double, std::chrono::microseconds::period>(25ms / sleep_scale));
speed_limiting_delta_err += duration_cast<microseconds>(
std::chrono::duration<double, std::chrono::microseconds::period>(
(current_system_time_us - previous_system_time_us) / sleep_scale));
speed_limiting_delta_err -= duration_cast<microseconds>(now - previous_walltime);
speed_limiting_delta_err =
std::clamp(speed_limiting_delta_err, -max_lag_time_us, max_lag_time_us);
if (speed_limiting_delta_err > microseconds::zero()) {
std::this_thread::sleep_for(speed_limiting_delta_err);
auto now_after_sleep = Clock::now();
speed_limiting_delta_err -= duration_cast<microseconds>(now_after_sleep - now);
now = now_after_sleep;
}
previous_system_time_us = current_system_time_us;
previous_walltime = now;
}
} // namespace Core