Latency Reduction Controller (LRC)

Windows-first foreground latency & jitter optimizer with a transparent control law:

• Shadow mode: observe decisions safely
• Active mode: adjust per-process priorities (CPU, I/O) with guardrails
• Adaptive to Windows updates via runtime capability detection & safe fallbacks
• MSIX packaging for easy install; PyInstaller-built Win32 payload

Dual-licensed: GPLv3 (public) or Commercial (proprietary use). See DUAL-LICENSING.md.

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How it works

LRC samples system load (CPU/GPU/RAM/DISK/NET), computes a bounded contention signal per resource, and aggregates a Prioritized Resource Contention Index (PRCI) that emphasizes the foreground task. When PRCI crosses a threshold (with hysteresis), LRC:

• Boosts likely-foreground processes (CPU priority up)
• Throttles heavy background contributors (CPU priority down, I/O priority lower)

All changes use documented, user-space Windows APIs and enforce minimum shares and recovery to avoid starvation.

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Quickstart (development)

python -m venv .venv
.\.venv\Scripts\Activate.ps1
pip install -U pip
pip install -e ".[dev]"

Run shadow mode (observe only)

python -m lrc.cli --mode shadow

Run active mode (apply safe adjustments)

python -m lrc.cli --mode active

By default, LRC avoids system processes and only changes priorities for apps owned by your user session.

Benchmark helpers (optional)

Install external tools for richer load gen (e.g. diskspd, iperf3, ffmpeg), then:

python .\scripts\bench\run_bench.py --collect

Outputs summary CSV to reports/bench_summary.csv when --collect is provided.

Build Win32 binary & MSIX

Build the payload (Win32 exe via PyInstaller):

pip install pyinstaller
pyinstaller --onefile --name lrc.exe src\lrc\cli.py
mkdir dist\lrc-win
move .\dist\lrc.exe dist\lrc-win\lrc.exe

Pack an unsigned MSIX (requires Windows 10/11 SDK makeappx):

.\packaging\msix\make_msix.ps1 -BuildDir "dist\lrc-win" -Out "LRC-App.msix"

Sign & install for dev sideloading:

.\packaging\msix\sign_msix.ps1 -Msix "LRC-App.msix" -Pfx "dev_signing.pfx" -Password "Passw0rd!"
.\packaging\msix\install_msix.ps1 -Msix "LRC-App.msix" -Pfx "dev_signing.pfx" -Password "Passw0rd!"

For production, sign with a trusted code-signing certificate; end users must trust the cert to install MSIX packages.

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Adaptive to Windows updates

LRC probes capabilities at runtime:

• Windows build version (to gate features if APIs change)
• Presence of pywin32 (CPU priority), psutil.ionice (I/O priority), pynvml (GPU telemetry)
• Safe fallbacks if a capability is missing (observe-only, or CPU-only adjustments)

This capability-first approach reduces breakage risk across Windows updates. When a capability degrades, LRC drops to a less-invasive behavior rather than failing.

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Safety model

• No kernel hooks, no process injection—only documented user-space APIs (SetPriorityClass, ionice).
• System allowlist prevents touching critical OS/AV/EDR processes.
• Hysteresis & rate limits avoid oscillations.
• Recovery raises background shares when the system is calm.

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Licensing

• GPLv3 (public): strong copyleft. Great for community users and academic settings.
• Commercial license: proprietary terms for closed-source integration or OEM bundling. See LICENSE-COMMERCIAL.md and contact sales@worlddatafilter.com.

Refer to DUAL-LICENSING.md for a summary of the two-track model.

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Roadmap

• Real foreground detection (active window → owning process tree)
• Per-process GPU & Disk attribution (where available)
• Profiles (Gaming/Creator/Enterprise) and UI panel
• WinGet/Chocolatey manifests; Microsoft Store submission
• Signed MSIX & MSI (optional admin service build)

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Contributing

Planned contributions require a CLA or Developer Certificate of Origin (DCO). Details to come in future updates.