siomon

A comprehensive Linux hardware information and real-time sensor monitoring tool. Single static binary, no runtime dependencies.

Run sio to launch an interactive TUI dashboard that polls all kernel-exported sensors in real time with min/max/avg tracking, configurable alerts, and CSV logging. Use subcommands like sio cpu, sio gpu, or sio storage for one-shot hardware information.

Install

Ubuntu 24.04 / 25.10 (PPA)

sudo apt update
sudo apt install software-properties-common
sudo add-apt-repository ppa:level1techs/siomon
sudo apt update
sudo apt install siomon

Arch Linux (AUR)

# Using an AUR helper (e.g., paru, yay)
paru -S siomon

Nix

# NixOS (add to configuration.nix)
environment.systemPackages = [ pkgs.siomon ];

# Non-NixOS / nix profile
nix profile install nixpkgs#siomon

# Temporary shell
nix-shell -p siomon

More installation options are planned. If you'd like to help package siomon for other distributions, see issue #4.

Quick Start

# Interactive TUI sensor monitor (default)
sio

# TUI with custom polling interval (ms)
sio --interval 500

# TUI with CSV logging
sio --log sensors.csv

# Sensor alerts
sio --alert "hwmon/nct6798/temp1 > 80" --alert "hwmon/nct6798/fan1 < 100 @60s"

# Specific sections
sio cpu
sio gpu
sio memory
sio storage
sio network
sio pci
sio pcie           # PCIe link details
sio audio
sio usb
sio battery
sio board

# JSON output (pipe to jq, store, etc.)
sio -f json
sio cpu -f json

# HTML report
sio -f html > report.html

# XML output
sio -f xml > report.xml

# One-shot sensor snapshot
sio sensors
sio sensors -f json

# Full access (SMART, DMI serials, MSR)
sudo sio

Features

Hardware Information (one-shot)

• CPU -- brand, microarchitecture codename, topology (packages/dies/cores/threads), cache hierarchy, feature flags (SSE through AVX-512, AMX), frequency, vulnerability details with mitigation status. Supports x86_64 (via CPUID) and aarch64 (via MIDR_EL1/procfs), including heterogeneous big.LITTLE configurations.
• Memory -- total/available/swap, per-DIMM details (manufacturer, part number, speed, ECC) via custom SMBIOS parser (no dmidecode dependency)
• Motherboard -- board vendor/model, BIOS version/date, UEFI/Secure Boot status, chipset identification, Intel ME firmware version
• GPU -- NVIDIA (via NVML), AMD (via amdgpu sysfs), Intel (via i915/xe sysfs); VRAM, clocks, power limit, PCIe link, display outputs, EDID monitor info
• Storage -- NVMe and SATA devices with model, serial, firmware, capacity; NVMe SMART health data (temperature, wear, hours, errors) via direct ioctl
• Network -- physical adapters with driver, MAC, link speed, IP addresses, NUMA node
• Audio -- HDA/USB audio devices with codec identification
• USB -- device tree with VID:PID, manufacturer, product, speed
• Battery -- charge status, wear level, cycle count, chemistry (laptops)
• PCI -- full bus enumeration with human-readable names from the PCI ID database (25,000+ devices)
• PCIe -- dedicated link analysis: negotiated vs max generation and width per device

Real-time Sensor Monitoring (TUI)

• hwmon -- all kernel-exported sensors: temperatures, fan speeds, voltages, power, current
• CPU -- per-core frequency and utilization
• GPU -- temperature, fan speed, power draw, core/memory clocks, utilization, VRAM usage (NVIDIA via NVML, AMD via sysfs); Tegra integrated GPU frequency and load via devfreq
• RAPL -- CPU package power consumption
• Tegra -- hardware engine clocks and state (APE, DLA, VIC, NVENC, etc.) on NVIDIA Jetson platforms
• Disk -- per-device read/write throughput
• Network -- per-interface RX/TX throughput
• Tracking -- min/max/average for every sensor across the monitoring session
• Collapsible groups -- groups with 32+ sensors auto-collapse; toggle with Enter/Space; collapsed groups show summary min/max/avg
• Alerts -- configurable threshold alerts (--alert "hwmon/nct6798/temp1 > 80 @30s")
• CSV logging -- record sensor data to file while monitoring (--log sensors.csv)
• Board-specific labels -- built-in label overrides for popular boards; user overrides via config file

Output Formats

• Pretty-printed text summary (default for subcommands)
• JSON (-f json)
• XML (-f xml)
• HTML report (-f html) -- self-contained dark-themed report with color-coded vulnerability status
• Per-section views (sio cpu, sio gpu, sio storage, sio pcie, etc.)
• Sensor snapshot (sio sensors)

Configuration

• Config file at ~/.config/siomon/config.toml for persistent preferences
• Sensor label overrides (built-in board mappings + user custom labels)

TUI Keybindings

Key	Action
q / Esc	Quit (or clear active filter if one is set)
/	Enter search/filter mode
Up / Down / j / k	Navigate between groups
Enter / Space	Toggle collapse/expand group
c	Collapse all groups
e	Expand all groups
PageUp / PageDown	Scroll 20 rows
Home / End	Jump to top/bottom
Mouse scroll	Scroll 3 lines

In filter mode (after pressing /):

Key	Action
any character / Space	Append to search query
Backspace	Delete last character
Enter	Confirm filter and return to normal navigation
Esc	Clear filter and exit filter mode

Runtime Dependencies

sio has zero mandatory runtime dependencies. Everything is read from kernel interfaces.

Optional Runtime

Component	What it enables	Package
NVIDIA driver	GPU name, VRAM, clocks, temp, power, utilization	libnvidia-compute (provides libnvidia-ml.so.1)
dmidecode	Per-DIMM memory details (manufacturer, part number, timings)	dmidecode
msr kernel module	CPU TDP, turbo ratios, C-states, perf limiters	modprobe msr
i2c-dev kernel module	SPD/XMP memory timing data	modprobe i2c-dev
drivetemp kernel module	SATA drive temperatures via hwmon	modprobe drivetemp

Privilege Model

sio runs without root and gracefully degrades:

Access Level	Available
Non-root	CPU info, hwmon sensors, GPU (NVML + sysfs), PCI/USB, network, disk basic info, DMI non-restricted fields
Root / sudo	+ Full DMI (serials, UUID), SMART data, NVMe health, MSR access, RAPL power, SPD timings

Fields requiring elevation show [requires root] or are omitted.

Running --direct-io Without Root

--direct-io needs raw hardware access. The recommended path is the sinfo_io kernel module (/dev/sinfo_io), which avoids direct /dev/port access.

1. Create a dedicated group:

sudo groupadd -f siomon

2. Add your user to that group:

sudo usermod -aG siomon "$USER"

3. Install a udev rule:

echo 'KERNEL=="sinfo_io", MODE="0660", GROUP="siomon"' | sudo tee /etc/udev/rules.d/99-siomon-sinfo-io.rules

4. Reload rules and trigger:

sudo udevadm control --reload-rules
sudo udevadm trigger --name-match=sinfo_io

5. Re-login (or reboot) so new group membership applies.

Then verify:

ls -l /dev/sinfo_io
sio sensors --direct-io

If /dev/sinfo_io is missing, the module is not loaded for your current kernel. Load/install sinfo_io first (DKMS or manual module install).

Troubleshooting:

• sio says Cannot open /dev/port for Super I/O detection and no superio/* sensors: --direct-io could not access either /dev/sinfo_io or /dev/port.
• /dev/sinfo_io is missing: load the module for the running kernel (sudo modprobe sinfo_io), or install/rebuild it (DKMS/manual) for the current uname -r.
• modprobe: FATAL: Module sinfo_io not found: the module is not installed for this kernel version. Rebuild/install sinfo_io against the currently running kernel, then run sudo depmod -a.
• /dev/sinfo_io exists but is root:root or mode 0600: udev rule did not apply. Re-run udevadm control --reload-rules and udevadm trigger --name-match=sinfo_io, or reload the module.
• User is in siomon group but access still denied: session has stale group memberships. Log out/in (or reboot), then verify with id.
• Board hwmon driver exists but sensors still do not appear: some drivers only bind with a force flag (example: sudo modprobe nct6683 force=1 on ASRock Z890 Nova WiFi). Use only when you have confirmed it matches your board/chip.
• Very new board, older kernel: support for newer Super I/O / hwmon chips usually lands in newer kernels first; older LTS kernels often lack those IDs unless your distro backports them.

Board Notes

• ASRock Z890 Nova WiFi -- board fan telemetry is exposed by an NCT6686D-class companion controller. On current kernels this requires loading the in-tree nct6683 hwmon driver with force=1:

sudo modprobe nct6683 force=1

Once loaded, the board fans appear under hwmon/nct6686.

Building

Prerequisites

• Rust 1.88+ (edition 2024)
• Linux (kernel 4.x+ for full sysfs support; 5.x+ recommended)
• Standard build tools (gcc or cc for libc linking)

Build

cargo build --release

The binary is at ./target/release/sio (~5.3 MB with all features, statically linked PCI ID database).

Cross-compilation

# For a different Linux target
rustup target add aarch64-unknown-linux-gnu
cargo build --release --target aarch64-unknown-linux-gnu

Contributing

See CONTRIBUTING.md for project-specific details and how to contribute.

Packaging

Distribution packages are built and published automatically when a version tag is pushed. See PACKAGING.md for setup and configuration.

• AUR: Workflow queries the AUR API and auto-increments pkgrel when re-publishing the same version. See packaging/aur/.
• PPA: Workflow queries the Launchpad API and auto-increments the packaging revision to avoid upload conflicts. See packaging/launchpad/.

License

MIT