GitHub Action - Runner Fetch

GitHub Action to inspect and continuously monitor GitHub Actions runner VMs.

• Environment, OS distribution, kernel, architecture, packages, and toolcache
• Hardware topology and CPU specifications
• Storage topology, partitions, filesystem formats, and free space
• Recursive directory tree via dust
• Continuous resource saturation monitoring (CPU %, RAM, Disk)
• Automatic crash / Out-Of-Memory (OOM) autopsy diagnostics
• Dual-consumption: formatted Markdown and SVG sparklines in $GITHUB_STEP_SUMMARY for humans, structured JSON and OpenMetrics (metrics.prom) for machines

Usage

steps:
  - name: Fetch & Monitor Runner
    id: fetch
    uses: Malix-Labs/GitHub-Action_Runner-Fetch@v2
    with:
      monitor: true
      disk-tree: true
      sample-interval: 2
      export-prometheus: true

  - name: Your Real CI Workload
    run: |
      echo "Running build and test steps..."
      cargo build --release

  - name: Inspect Runner Telemetry
    if: always()
    run: |
      echo "Peak Memory: ${{ steps.fetch.outputs.peak_memory_mb }} MB"
      echo "Avg CPU: ${{ steps.fetch.outputs.avg_cpu_percent }}%"
      echo "OOM Detected: ${{ steps.fetch.outputs.oom_detected }}"

Inputs

Input	Description	Default
monitor	Enable continuous background resource monitoring	true
disk-tree	Build recursive directory tree via dust	true
sample-interval	Sampling interval in seconds	2
export-prometheus	Generate OpenMetrics / Prometheus file	true

Outputs

Output	Description
environment	JSON containing OS, distro, kernel, architecture, hostname, runner name, and uptime
cpu	JSON containing CPU model, cores, threads, and cache levels
storage	JSON containing block devices, partitions, filesystem formats, and free space
hardware	JSON containing hardware topology and RAM specs
disk_tree_path	Path to JSON file containing full recursive filesystem tree (dust -j)
artifact_name	Deterministic name of the disk tree artifact
summary	JSON containing aggregate utilization metrics and autopsy data
peak_memory_mb	Peak RAM usage in megabytes observed during the job
avg_cpu_percent	Average CPU utilization percentage across the job
disk_consumed_mb	Net disk space consumed in megabytes
oom_detected	Boolean indicating whether a Linux kernel OOM kill occurred

Why is Node 24 used instead of a pure composite action?

GitHub Actions does not support post: hooks for composite actions (actions/runner#1478).

Without a post step, users would be forced to manually add an extra teardown step with if: always() at the bottom of every workflow. To keep your workflows clean (one step only), we use a minimal 10-line Node 24 wrapper strictly to hook into GitHub's runner lifecycle. All fetching, sampling, and reporting logic remains 100% shell scripts.

Please upvote the upstream issue if you want native composite post-step support!

Examples

See workflow runs in action: Fetch & Monitor Workflows