System Metrics

Probestyx collects a comprehensive set of system metrics out-of-the-box. This page documents all available system metrics.

Enabling System Metrics

Add metrics to your config.yaml:

system:
  enabled: true
  metrics:
    - cpu_usage_percent
    - ram_usage_percent
    - disk_usage_percent

CPU Metrics

cpu_usage_percent

Overall CPU utilization across all cores.

• Type: Float
• Unit: Percentage (0-100)
• Example: 45.2
• Use case: Monitor overall CPU load

metrics:
  - cpu_usage_percent

cpu_usage_per_core

CPU utilization for each core individually.

• Type: Array of floats
• Unit: Percentage per core (0-100)
• Example: [42.1, 38.5, 51.3, 44.7]
• Use case: Identify if specific cores are bottlenecked

metrics:
  - cpu_usage_per_core

cpu_count

Number of logical CPU cores (includes hyperthreading).

• Type: Integer
• Unit: Count
• Example: 8
• Use case: Normalize CPU metrics, capacity planning

metrics:
  - cpu_count

cpu_count_physical

Number of physical CPU cores (excludes hyperthreading).

• Type: Integer
• Unit: Count
• Example: 4
• Use case: Understanding actual hardware capacity

metrics:
  - cpu_count_physical

cpu_load_1min

System load average over 1 minute.

• Type: Float
• Unit: Load
• Example: 2.5
• Use case: Short-term load monitoring
• Note: Values > cpu_count indicate overload

metrics:
  - cpu_load_1min

cpu_load_5min

System load average over 5 minutes.

• Type: Float
• Unit: Load
• Example: 1.8
• Use case: Medium-term load trends

metrics:
  - cpu_load_5min

cpu_load_15min

System load average over 15 minutes.

• Type: Float
• Unit: Load
• Example: 1.2
• Use case: Long-term load trends, baseline monitoring

metrics:
  - cpu_load_15min

Memory Metrics

ram_usage_percent

RAM utilization as a percentage of total memory.

• Type: Float
• Unit: Percentage (0-100)
• Example: 67.8
• Use case: Monitor memory pressure

metrics:
  - ram_usage_percent

available_ram_mb

Amount of RAM available for applications.

• Type: Float
• Unit: Megabytes
• Example: 8192.5
• Use case: Check if system has free memory

metrics:
  - available_ram_mb

total_ram_mb

Total installed RAM.

• Type: Float
• Unit: Megabytes
• Example: 16384.0
• Use case: Capacity planning, normalization

metrics:
  - total_ram_mb

ram_cached_mb

RAM used for file system cache.

• Type: Float
• Unit: Megabytes
• Example: 4096.2
• Use case: Understanding memory usage breakdown

metrics:
  - ram_cached_mb

ram_buffers_mb

RAM used for buffers.

• Type: Float
• Unit: Megabytes
• Example: 512.8
• Use case: Low-level memory analysis

metrics:
  - ram_buffers_mb

swap_usage_percent

Swap space utilization.

• Type: Float
• Unit: Percentage (0-100)
• Example: 15.3
• Use case: Detect memory pressure (high swap = problem)

metrics:
  - swap_usage_percent

swap_total_mb

Total swap space configured.

• Type: Float
• Unit: Megabytes
• Example: 8192.0
• Use case: Capacity planning

metrics:
  - swap_total_mb

swap_used_mb

Amount of swap currently in use.

• Type: Float
• Unit: Megabytes
• Example: 1024.5
• Use case: Monitor swap usage trends

metrics:
  - swap_used_mb

Disk Metrics

disk_usage_percent

Disk space utilization for the root filesystem.

• Type: Float
• Unit: Percentage (0-100)
• Example: 52.3
• Use case: Monitor disk space, trigger cleanup

metrics:
  - disk_usage_percent

available_disk_gb

Available disk space on root filesystem.

• Type: Float
• Unit: Gigabytes
• Example: 128.5
• Use case: Check remaining capacity

metrics:
  - available_disk_gb

total_disk_gb

Total disk capacity of root filesystem.

• Type: Float
• Unit: Gigabytes
• Example: 256.0
• Use case: Capacity planning

metrics:
  - total_disk_gb

inode_usage_percent

Percentage of inodes used on root filesystem.

• Type: Float
• Unit: Percentage (0-100)
• Example: 12.5
• Use case: Detect filesystem limits (many small files)

metrics:
  - inode_usage_percent

disk_read_bytes

Cumulative bytes read from disk since boot.

• Type: Integer
• Unit: Bytes
• Example: 1073741824000
• Use case: Calculate read rates over time

metrics:
  - disk_read_bytes

disk_write_bytes

Cumulative bytes written to disk since boot.

• Type: Integer
• Unit: Bytes
• Example: 536870912000
• Use case: Calculate write rates over time

metrics:
  - disk_write_bytes

disk_read_bytes_per_sec

Current disk read rate.

• Type: Float
• Unit: Bytes per second
• Example: 1048576.0
• Use case: Monitor disk I/O performance

metrics:
  - disk_read_bytes_per_sec

disk_write_bytes_per_sec

Current disk write rate.

• Type: Float
• Unit: Bytes per second
• Example: 524288.0
• Use case: Monitor disk I/O performance

metrics:
  - disk_write_bytes_per_sec

disk_read_count

Cumulative read operations since boot.

• Type: Integer
• Unit: Count
• Example: 1500000
• Use case: Calculate IOPS over time

metrics:
  - disk_read_count

disk_write_count

Cumulative write operations since boot.

• Type: Integer
• Unit: Count
• Example: 800000
• Use case: Calculate IOPS over time

metrics:
  - disk_write_count

Network Metrics

network_bytes_sent

Cumulative bytes sent across all interfaces since boot.

• Type: Integer
• Unit: Bytes
• Example: 10737418240
• Use case: Calculate send rates over time

metrics:
  - network_bytes_sent

network_bytes_recv

Cumulative bytes received across all interfaces since boot.

• Type: Integer
• Unit: Bytes
• Example: 21474836480
• Use case: Calculate receive rates over time

metrics:
  - network_bytes_recv

network_bytes_sent_per_sec

Current network send rate.

• Type: Float
• Unit: Bytes per second
• Example: 102400.0
• Use case: Monitor bandwidth usage

metrics:
  - network_bytes_sent_per_sec

network_bytes_recv_per_sec

Current network receive rate.

• Type: Float
• Unit: Bytes per second
• Example: 204800.0
• Use case: Monitor bandwidth usage

metrics:
  - network_bytes_recv_per_sec

network_packets_sent

Cumulative packets sent across all interfaces.

• Type: Integer
• Unit: Count
• Example: 5000000
• Use case: Calculate packet rates

metrics:
  - network_packets_sent

network_packets_recv

Cumulative packets received across all interfaces.

• Type: Integer
• Unit: Count
• Example: 7500000
• Use case: Calculate packet rates

metrics:
  - network_packets_recv

network_errors_in

Cumulative inbound network errors.

• Type: Integer
• Unit: Count
• Example: 12
• Use case: Monitor network health

metrics:
  - network_errors_in

network_errors_out

Cumulative outbound network errors.

• Type: Integer
• Unit: Count
• Example: 5
• Use case: Monitor network health

metrics:
  - network_errors_out

active_connections

Number of active TCP connections.

• Type: Integer
• Unit: Count
• Example: 42
• Use case: Monitor connection usage, detect connection leaks

metrics:
  - active_connections

System Information

system_uptime_seconds

Time since system boot.

• Type: Integer
• Unit: Seconds
• Example: 86400
• Use case: Track system restarts, uptime monitoring

metrics:
  - system_uptime_seconds

boot_time_unix

System boot time as Unix timestamp.

• Type: Integer
• Unit: Unix timestamp
• Example: 1704067200
• Use case: Calculate uptime, track reboots

metrics:
  - boot_time_unix

os_platform

Operating system platform.

• Type: String
• Example: "linux", "darwin", "windows"
• Use case: System inventory, OS-specific logic

metrics:
  - os_platform

os_version

Operating system version.

• Type: String
• Example: "Ubuntu 22.04.3 LTS"
• Use case: System inventory, version tracking

metrics:
  - os_version

hostname

System hostname.

• Type: String
• Example: "web-server-01"
• Use case: Identify which server metrics come from

metrics:
  - hostname

kernel_version

Kernel version string.

• Type: String
• Example: "5.15.0-91-generic"
• Use case: System inventory, compatibility checking

metrics:
  - kernel_version

process_count

Number of running processes.

• Type: Integer
• Unit: Count
• Example: 156
• Use case: Monitor system load, detect process leaks

metrics:
  - process_count

Common Metric Combinations

Basic Monitoring

Essential metrics for general server monitoring:

system:
  enabled: true
  metrics:
    - cpu_usage_percent
    - ram_usage_percent
    - disk_usage_percent
    - network_bytes_sent_per_sec
    - network_bytes_recv_per_sec
    - system_uptime_seconds

Performance Monitoring

Detailed metrics for performance analysis:

system:
  enabled: true
  metrics:
    - cpu_usage_percent
    - cpu_usage_per_core
    - cpu_load_1min
    - cpu_load_5min
    - ram_usage_percent
    - available_ram_mb
    - disk_read_bytes_per_sec
    - disk_write_bytes_per_sec
    - network_bytes_sent_per_sec
    - network_bytes_recv_per_sec

Capacity Planning

Metrics for capacity and resource planning:

system:
  enabled: true
  metrics:
    - cpu_count
    - total_ram_mb
    - total_disk_gb
    - available_disk_gb
    - disk_usage_percent
    - ram_usage_percent

Troubleshooting

Metrics useful for diagnosing issues:

system:
  enabled: true
  metrics:
    - cpu_usage_percent
    - cpu_load_1min
    - ram_usage_percent
    - swap_usage_percent
    - disk_usage_percent
    - inode_usage_percent
    - network_errors_in
    - network_errors_out
    - active_connections
    - process_count

Minimal Footprint

Only the most essential metrics:

system:
  enabled: true
  metrics:
    - cpu_usage_percent
    - ram_usage_percent
    - disk_usage_percent

Understanding Metric Values

CPU Load

CPU load averages represent the number of processes waiting for CPU time:

• Load < CPU count: System is healthy
• Load = CPU count: System is at capacity
• Load > CPU count: System is overloaded

Example with 4 cores:

• Load of 2.0: Good (50% capacity)
• Load of 4.0: At capacity
• Load of 8.0: Overloaded (2x capacity)

Memory Usage

High memory usage isn't always bad (caching), but watch for:

• High RAM usage + high swap: Memory pressure
• Rapidly growing memory: Potential leak
• Low available RAM: May need more memory

Disk I/O

Rate metrics show current activity:

• Spikes are normal
• Sustained high rates may indicate bottleneck
• Compare with application workload

Network

• Monitor trends over time
• High error counts indicate problems
• Correlate with application traffic patterns

Platform Differences

Some metrics behave differently across platforms:

Metric	Linux	macOS	Windows
cpu_load_*	✅ Full support	✅ Full support	⚠️ Limited
ram_buffers_mb	✅ Available	❌ Not applicable	❌ Not applicable
inode_usage_percent	✅ Available	✅ Available	❌ Not applicable
All other metrics	✅ Full support	✅ Full support	✅ Full support

Next Steps

• Configuration - Learn how to configure metrics
• Custom Metrics - Add your own custom metrics
• Integration - Send metrics to Logstyx