# npu-monitor: a system tray that knows what hardware each box actually has

*2026-08-21*

> A KDE tray monitor for CPU, GPU, and NPU utilization across multiple LAN hosts — with dynamic device discovery, mDNS auto-registration, and live bar-graph pop-outs.


Every multi-host monitoring tool I tried assumed homogeneous hardware: one GPU, maybe two, same on every machine. My LAN doesn't work like that — one box has an AMD APU iGPU plus a Ryzen AI NPU, another has an AMD R9700 *and* an NVIDIA RTX 5060 Ti. So `npu-monitor` treats the device list as dynamic: each host reports its own real silicon and the tray renders whatever arrives.

The numbers come from the actual kernel interfaces, not screen-scraping: ROCm sysfs (`gpu_busy_percent`) for AMD cards, `nvidia-smi` for CUDA, `/proc/stat` deltas for CPU, and a raw `DRM_IOCTL_AMDXDNA_GET_INFO` ioctl against `/dev/accel/accel0` — using the real 168-byte sensor struct from the kernel UAPI — for the NPU's utilization columns.

Features:

- KDE/X11 system-tray tooltip with live CPU + every GPU + optional NPU per host, polled every 2 seconds
- Double-click pop-out windows with live bar graphs per host, values rendered inside the bars
- **Zero-config new hosts**: each server advertises itself over mDNS (`_gpu-monitor._tcp`) via avahi; the tray discovers it live, no restart, no config edit
- Hostname-derived identity dedupes `wimpy` / `wimpy.local` / `wimpy.home.lan` into one entry
- Server side is stdlib-only Python — no pip install on monitored machines
- Every poll appends to a long-format CSV (timestamp, host, device, util) locally and on the desktop
- APU iGPUs are dropped when a discrete GPU is present, so the list stays meaningful
- `--headless` mode still polls, logs, and prints — for boxes without a GUI session

Source: [github.com/rahlquist/npu-monitor](https://github.com/rahlquist/npu-monitor) · MIT licensed.