PerfPulse

English · Português

Lightweight, injection-free game performance recorder for Windows: it sits in the tray, notices on its own when a game starts, records FPS/frametime and sensors during the session and, when the game closes, produces an offline HTML report with a summary, averages, medians, a smoothness score, a bottleneck diagnosis (what the offender was and when) and energy consumed by the GPU and CPU.

• A single PerfPulse.exe (~0.9 MB, C++20/Win32, no external runtime).
• ~0.7% of one core while recording; ~3 MB of RAM when idle.
• On hybrid CPUs (Intel 12th gen+), it runs in efficiency mode (EcoQoS) and leaves the P-cores to the game.

Download

Grab PerfPulse-vX.Y.Z-win64.zip from the latest release, extract it anywhere and run PerfPulse.exe. No installer, no runtime to install.

The exe is not code-signed, so Windows SmartScreen may show "Windows protected your PC": click More info → Run anyway. For CPU temperature and power, also install the PawnIO driver (winget install namazso.PawnIO).

Example report

A real 2h34 session of Wardogs (RTX 3080 Ti + i9-14900K, 1440p @ 180 Hz). The full report is in docs/examples/: download the .html and open it in a browser, it works offline.

More sections: performance timeline, sensors, energy and stutters

How it works

Stage	Technique
Game detection	Every 2 s: foreground window on the chosen monitor, covering the screen (fullscreen or borderless) and presenting ≥ 10 frames/s for N seconds. "Always"/"never monitor" lists take priority.
FPS and frametime	Real-time ETW consumer (DXGI, D3D9 and DxgKrnl, the same method as PresentMon), with event ID filtering in the kernel. Every frame is recorded, which gives correct 1% and 0.1% lows.
NVIDIA GPU	NVML (usage, temperature, clocks, power, fan, VRAM, limiter) + NVAPI (hotspot, VRAM junction, voltage).
AMD/Intel GPU	WDDM: "GPU Engine"/"GPU Adapter Memory" counters + D3DKMTQueryAdapterInfo (temperature, clocks, fan, voltage).
CPU	Per-core usage and the game's busiest thread (NtQuerySystemInformation); effective clock (PDH); temperature and power via PawnIO → HWiNFO → LibreHardwareMonitor.
Report	Analysis in C++, a single HTML file with embedded canvas charts (no internet needed), PT-BR/EN, light/dark.

Data stays in memory while you play: nothing is written to disk until the session ends.

Requirements

• Windows 10 21H2+ or Windows 11, x64.
• Run as administrator (the manifest already requests it). Present ETW and PawnIO require elevation. The Start with Windows option creates an elevated scheduled task, so no UAC prompt appears at logon.
• For CPU temperature and power: PawnIO installed + modules in the modules\ folder next to the exe (tools\fetch_pawnio_modules.ps1). Alternatives: HWiNFO with Shared Memory Support or LibreHardwareMonitor running.

Building

Prerequisites: Visual Studio 2022 Build Tools (C++ workload, Windows SDK 10.0.22621+, CMake and Ninja).

.\tools\fetch_pawnio_modules.ps1   # once: signed PawnIO modules
.\tools\build.ps1                  # Release + tests -> build\release\PerfPulse.exe
.\tools\build.ps1 -Config debug
.\tools\package.ps1                # Release + tests -> build\PerfPulse-vX.Y.Z-win64.zip

Or directly with CMake, from a Developer PowerShell:

cmake --preset release
cmake --build --preset release
ctest --preset release

The repository can live on a UNC path (\\wsl.localhost\...); build.ps1 maps a drive letter during the build, because CMake and Ninja don't handle UNC paths well.

Usage

1. Run PerfPulse.exe. On first run the settings window opens; after that it goes straight to the tray.
2. Play. The icon turns amber while it confirms the game and gets a red dot while recording.
3. Close the game (or use Stop recording in the menu): the report goes to Documents\PerfPulse\Reports and the index.html in that folder compares all sessions per game.

Tray: double-click opens the settings; right-click shows the menu (enable/pause, latest report, history, folder, demo report, exit).

Command line

Argument	Effect
--autostart	Used by the logon task (doesn't open the settings on first run).
--diag [--out file.txt]	Diagnostics: sensor sources, 3 samples and per-process present rate for 10 s.
--demo-report [--out file.txt]	Generates a report from an 18-minute synthetic session.
--exit	Asks the running instance to save the current session's report and exit.
--reanalyze report.html [--to new.html]	Re-runs the bottleneck analysis of an old report with the current rules and template (in place, unless --to is given) and updates the history next to it. Frame statistics stay as originally recorded, because raw frames are not saved.

The report

• Summary: game, date, duration (active × background time), hardware, resolution, API and V-Sync.
• KPIs: average and median FPS, 1% and 0.1% lows, median/p99 frametime, stutters per minute, Wh and FPS per watt.
• Smoothness score from 0 to 100 (S/A/B/C/D): local consistency (45%), stutters per minute (35%) and frame-to-frame regularity (20%).
• Bottleneck: each sample is classified as GPU, GPU (throttling), CPU, CPU (thermal), VRAM, RAM, FPS cap, undetermined, loading or background. The report shows the timeline, the main offender and specific tips.
• Stutters: every hitch, with its timestamp and the hardware state at that moment.
• Sensors: one chart per chosen metric, with average, median, minimum, maximum and p95.
• Energy: GPU and CPU Wh (only what is actually measured), average and peak power, energy per frame.

Layout

src/
  core/       config, JSON, i18n, metrics, paths, log
  capture/    ETW present consumer
  detection/  game detector, monitors, process info
  sensors/    NVIDIA, generic WDDM, CPU, PawnIO/HWiNFO/LHM, memory
  session/    session data model and recorder
  analysis/   frame statistics, stutter, score, bottleneck, energy
  report/     JSON payload, HTML generator, history, demo session
  app/        tray, settings window, theme, autostart, diagnostics
resources/    icon, manifest, HTML templates for the report and history
tests/        unit tests (ctest) and a D3D11 "fake game" for end-to-end tests
tools/        build, icon and PawnIO module download
docs/         architecture and coding style

See docs/architecture.md and docs/coding-style.md.

Known limitations (v0.1)

• No in-game overlay (phase 2).
• On AMD/Intel, GPU power in watts isn't exposed by WDDM: it stays "not measured" until ADLX/IGCL integration.
• Energy only covers the GPU and CPU package; motherboard, RAM, SSD, fans and PSU losses are left out.
• FPS = the application's Present call rate (like PresentMon's "FPS"), not frames shown by the monitor.

License

MIT. The PawnIO modules shipped in the release zip are LGPL-2.1.