Server Monitor (Oshi)

ArchSmith includes a built-in server monitoring dashboard powered by Oshi, providing real-time visibility into system resources directly from the admin panel.

Features

• CPU: Usage percentage, core count, model info
• Memory: Total, used, free, usage percentage
• JVM: Heap usage, non-heap usage, max memory, JVM version
• Operating System: Name, version, architecture
• Disk: Partition info, total space, used space, usage percentage
• Auto-refresh dashboard with configurable interval

Configuration

Enable or disable the monitor in your application YAML:

arch-smith:
  monitor:
    enabled: true    # Set to false to disable the /server-info endpoint

The monitor is enabled by default in the dev profile.

API Endpoint

Method	Endpoint	Description
GET	/admin-api/server-info	Returns current server metrics

Response Structure

{
  "cpu": {
    "cpuNum": 8,
    "total": 100.0,
    "sys": 12.5,
    "used": 35.2,
    "wait": 0.8,
    "free": 51.5
  },
  "memory": {
    "total": "16.00 GB",
    "used": "10.24 GB",
    "free": "5.76 GB",
    "usage": 64.0
  },
  "jvm": {
    "total": "512.00 MB",
    "max": "2048.00 MB",
    "free": "256.00 MB",
    "usage": 50.0,
    "version": "21.0.7",
    "home": "/usr/lib/jvm/java-21"
  },
  "sys": {
    "computerName": "archsmith-server",
    "osName": "Linux",
    "osArch": "amd64",
    "userDir": "/app"
  },
  "sysFiles": [
    {
      "dirName": "/",
      "sysTypeName": "ext4",
      "typeName": "Local Disk",
      "total": "100.00 GB",
      "free": "45.00 GB",
      "used": "55.00 GB",
      "usage": 55.0
    }
  ]
}

Frontend Dashboard

The monitoring page displays the server metrics in a visual dashboard with:

• Progress bars for CPU, memory, and JVM usage percentages
• Disk table showing all partitions with usage bars
• System info cards for OS and JVM details
• Auto-refresh button to periodically reload metrics

How It Works

1. The frontend calls GET /admin-api/server-info
2. The backend uses Oshi to query hardware and OS sensors
3. JVM metrics are collected from Runtime.getRuntime() and ManagementFactory
4. All data is formatted and returned as a single JSON response

Oshi is a pure Java library with no native dependencies, making it compatible with both JVM and Native Image (Liberica NIK) deployments.

Performance Notes

• Oshi queries are lightweight (~10ms per call)
• The endpoint is protected by authentication — only logged-in admins can access it
• Consider adjusting the frontend auto-refresh interval in production to avoid unnecessary load

Related Pages

• Configuration — enable/disable monitoring
• Docker Deployment — monitoring in containerized environments
• Log Management — application-level logging