sysmonitor-go

A terminal system dashboard for Linux. Written in Go with no external dependencies — everything is read straight from /proc and /sys.

Install

./install.sh

No privileges required. The script builds the binary and drops it in ~/.local/bin. If Go is not installed on the machine, it downloads it into ~/.local/go and uses it only for this build — nothing is added to your PATH, nothing is installed system-wide.

PREFIX=/opt/sysmonitor ./install.sh   # another destination
./uninstall.sh                        # remove the binary

If you already have a Go toolchain, one line is enough:

go install github.com/aluzed/sysmonitor-go/cmd/sysmonitor@latest

Then:

sysmonitor

The project is called sysmonitor-go, the command is sysmonitor — the suffix only distinguishes the repository, it is not something you should have to type every day. To change the command name, edit the NAME variable at the top of install.sh and uninstall.sh.

What it shows

Panel	Contents
COOLER	An ASCII CPU cooler drawn in polar coordinates, with blades that genuinely rotate. Fan speed and heatsink temperature.
CPU	Model, overall load, average and peak frequency, temperatures, turbo state, braille history graph.
CORES	One htop-style gauge per thread, with its individual frequency.
MEMORY	RAM and swap, cache and buffers, history.
DISKS	Usage per filesystem, read/write throughput, history.
SENSORS	Every hwmon temperature, every fan, network throughput.

Usage

sysmonitor              # full screen, 15 fps
sysmonitor -fps 30      # smoother animation
sysmonitor -fps 4       # frugal
sysmonitor -once        # a single frame on stdout
sysmonitor -w 120 -h 40 # force dimensions (handy with -once)
sysmonitor -version     # build version

Keys: q quit · p (or space) pause.

Layout

Three layouts, picked automatically from the terminal width:

• ≥ 114 columns — cooler and CPU side by side, then memory, disks and sensors in a row of three.
• 68 to 113 — sensors move to their own full-width row.
• < 68 — everything stacked in a single column.

The height is budgeted explicitly so the output lands exactly on the terminal height. When room runs short the core grid collapses to a compact line (one bar per thread), and panels that no longer fit are dropped rather than cut in half. Best experienced at 120 × 40 or larger.

Fans

Every fan*_input exposed by hwmon is read, whatever the chip and driver. Headers reading 0 rpm are hidden: they are almost always empty sockets, and they would fill the panel with nothing.

The cooler animation follows the CPU fan. When the driver provides no label, it falls back to the first fan on the board Super-I/O — fan1 is the CPU_FAN header by near-universal convention. The sensor being followed is named under the drawing, with an (assumed) marker when it is a guess. To force another header:

SYSMONITOR_CPU_FAN="fan2" sysmonitor

If no fan is readable at all, the cooler spins in proportion to CPU load and says so plainly (no sensor → CPU load).

Chips the kernel does not support

Common on Gigabyte boards. The in-tree it87 driver stops at it8628 and knows neither the IT8688E/IT8689E nor several other recent models. Symptom: no fans besides the GPU, and modprobe it87 stays silent.

The out-of-tree driver frankcrawford/it87 handles them. Install through DKMS so it is rebuilt on every kernel update:

git clone https://github.com/frankcrawford/it87.git
cd it87 && sudo ./dkms-install.sh
sudo modprobe it87
echo it87 | sudo tee /etc/modules-load.d/it87.conf   # load at boot

If the module loads but exposes nothing, ACPI is holding the chip. The ignore_resource_conflict=1 parameter overrides that for this driver only, which is preferable to a system-wide acpi_enforce_resources=lax. Use it knowingly: ACPI and the driver then poke the same registers.

ASUS and MSI boards generally use Nuvoton chips, supported out of the box by the in-tree nct6775 driver — nothing to install.

Portability

Nothing here is vendor-specific. /proc/stat, /proc/meminfo, /proc/diskstats and friends are universal; hwmon is enumerated dynamically, so unknown chips still show up under their raw name. Turbo state is read from cpufreq/boost (AMD) or intel_pstate/no_turbo (Intel), and CPU temperature from Tctl /Tdie (AMD) or Package (Intel).

The one AMD-flavoured item is the GPU utilisation percentage, which comes from gpu_busy_percent. On other GPUs that single field simply disappears from the display.

Files

File	Role
cmd/sysmonitor/collect.go	Reads /proc and /sys, computes deltas.
cmd/sysmonitor/render.go	24-bit colour, bars, braille graphs, ANSI-aware string measurement.
cmd/sysmonitor/cooler.go	Procedural rendering of the CPU cooler.
cmd/sysmonitor/main.go	Layout, display loop, terminal handling.
install.sh	Build and install, no privileges.
uninstall.sh	Remove the binary.

The sources live under cmd/sysmonitor/ rather than at the repository root so that go install produces a binary named sysmonitor, not sysmonitor-go.

To modify the program, read DEVELOPMENT.md: architecture, panel height contracts, ANSI rendering pitfalls, kernel source subtleties and test recipes.

Licence

MIT — see LICENSE. Do whatever you want with it.

Building by hand

go build -o sysmonitor ./cmd/sysmonitor

That is all: no dependencies, so no go mod download. install.sh merely adds -trimpath -ldflags "-s -w -X main.version=…", which takes the binary from 3.2 MB down to 2.2 MB and stamps in the version from git describe.

Binaries produced by go install carry no such stamp, so -version reads the module version back from the build info the toolchain embeds. Either way the command reports something meaningful.