SysInfo

A lightweight Elixir library for retrieving system metrics (CPU, RAM, Swap, Disk). Supports both Linux and macOS.

Unlike the standard :cpu_sup, SysInfo reads data directly from system files (/proc on Linux) or via system calls (sysctl, top on macOS), ensuring high accuracy and preventing false spikes caused by the collection process itself.

Installation

Add sys_info to your list of dependencies in mix.exs:

def deps do
  [
    {:sys_info, "~> 0.1.0"}
  ]
end

Usage

Get All Metrics at Once

SysInfo.info()
# => %{
#      cpu: 12.5,
#      ram: %{total: 17179869184, used: 8589934592, free: 8589934592, percent: 50.0},
#      swap: %{total: 2147483648, used: 1073741824, free: 1073741824, percent: 50.0},
#      disk: %{total: 494384795648, used: 200000000000, free: 294384795648, percent: 40.45}
#    }

CPU Usage

Returns the current CPU usage as a percentage.

SysInfo.cpu_usage()
# => 5.2

Note: On Linux, it takes two samples with a 100ms interval to calculate the delta accurately.

Memory Info (RAM)

Returns RAM usage details in bytes.

SysInfo.memory_info()
# => %{total: 17179869184, used: 8589934592, free: 8589934592, percent: 50.0}

Swap Info

Returns swap partition details in bytes.

SysInfo.swap_info()

Disk Info

Returns disk usage for the specified path (defaults to /) in bytes.

SysInfo.disk_info("/")

Platform Implementation

• Linux: Direct reading of /proc/stat and /proc/meminfo. This is the most efficient way with minimal overhead.
• macOS: Uses sysctl, vm_stat, and top. Since macOS lacks /proc, it utilizes native Darwin system utilities.