Kernel and OSI PI Integration

Input and output integration overview

The Kernel plugin collects various statistics about the Linux kernel, including context switches, page usage, and entropy availability.

This setup converts Telegraf into a lightweight PI Web API publisher, letting you push any Telegraf metric into the OSI PI System with a simple HTTP POST.

Integration details

Kernel

The Kernel plugin is designed exclusively for Linux systems and gathers essential kernel statistics that are not covered by other plugins. It primarily focuses on the metrics available in /proc/stat, as well as the entropy available from /proc/sys/kernel/random/entropy_avail. Additional functionalities include the capture of Kernel Samepage Merging (KSM) data and Pressure Stall Information (PSI), requiring Linux kernel version 4.20 or later. This plugin provides a comprehensive look into system behaviors, enabling better understanding and optimization of resource management and usage. The metrics it collects are critical for monitoring system health and performance.

OSI PI

OSI PI is an data management and analytics platform used in energy, manufacturing, and critical infrastructure. The PI Web API is its REST interface, exposing endpoints such as /piwebapi/streams/{WebId}/value that accept JSON payloads containing a Timestamp and Value. By pairing Telegraf’s flexible HTTP output with this endpoint, any metric Telegraf collects—SNMP counters, Modbus readings, Kubernetes stats—can be written directly into PI without installing proprietary interfaces. The configuration above authenticates with Basic or Kerberos, serializes each batch to JSON, and renders a minimal body template that aligns with PI Web API’s single-value write contract. Because Telegraf already supports batching, TLS, proxies, and custom headers, this approach scales from edge gateways to cloud VMs, allowing organizations to back-fill historical data, stream live telemetry, or mirror non-PI sources (e.g., Prometheus) into the PI data archive. It also sidesteps older SDK dependencies and enables hybrid architectures where PI remains on-prem while Telegraf agents run in containers or IIoT devices.

Configuration

Kernel

[[inputs.kernel]]
  ## Additional gather options
  ## Possible options include:
  ## * ksm - kernel same-page merging
  ## * psi - pressure stall information
  # collect = []

OSI PI

[[outputs.http]]
  ## PI Web API endpoint for writing a single value to a PI Point by Web ID
  url = "https://${PI_HOST}/piwebapi/streams/${WEB_ID}/value"

  ## Use POST for each batch
  method       = "POST"
  content_type = "application/json"

  ## Basic-auth header (base64-encoded "DOMAIN\\user:password")
  headers = { Authorization = "Basic ${BASIC_AUTH}" }

  ## Serialize Telegraf metrics as JSON
  data_format           = "json"
  json_timestamp_units  = "1ms"

  ## Render the JSON body that PI Web API expects
  body_template = """
  {{ range .Metrics -}}
  { "Timestamp": "{{ .timestamp | formatDate \"2006-01-02T15:04:05Z07:00\" }}", "Value": {{ index .fields 0 }} }
  {{ end -}}
  """

  ## Tune networking / batching if needed
  # timeout     = "10s"
  # batch_size  = 1

Input and output integration examples

Kernel

1. Memory Optimization through KSM: Utilize the KSM capabilities of this plugin to monitor memory usage patterns in your applications and dynamically adjust the memory allocation strategy based on shared page usage metrics. By analyzing the data collected, you can identify opportunities for consolidating memory and optimizing performance without manual intervention.

2. Real-time System Health Monitoring: Integrate the metrics collected by the Kernel plugin into a real-time dashboard that visualizes key kernel statistics including context switches, interrupts, and entropy availability. This setup allows system administrators to proactively respond to performance issues before they escalate into critical failures, ensuring smooth operation of Linux servers.

3. Enhanced Anomaly Detection: Combine the data from this plugin with machine learning models to predict and detect anomalies in kernel behavior. By continuously monitoring metrics like process forking rates and entropy levels, you can implement an adaptive alerting system that triggers on performance anomalies, allowing for quick responses to potential issues.

4. Resource Usage Patterns Analysis: Use the Pressure Stall Information collected by the plugin to analyze resource usage patterns over time and identify potential bottlenecks under load conditions. By adjusting application performance based on the PSI metrics, you can improve overall resource management and maintain service reliability under varying workloads.

OSI PI

1. Remote Pump Stations Telemetry Bridge: Install Telegraf on edge gateways at oil-field pump stations, gather flow-meter and vibration readings over Modbus, and POST them to the PI Web API. Operations teams view real-time data in PI Vision without deploying heavyweight PI interfaces, while bandwidth-friendly batching keeps satellite links economical.

2. Green-Energy Micro-Grid Dashboard: Export inverter, battery, and weather metrics from MQTT into Telegraf, which relays them to PI. PI AF analytics can calculate real-time power balance and feed a campus dashboard; historical deltas inform sustainability reports.

3. Brownfield SCADA Modernization: Legacy PLCs logged to CSV are ingested by Telegraf’s tail input; each row is parsed and immediately sent to PI via HTTP, creating a live data stream that co-exists with archival files while the SCADA upgrade proceeds incrementally.

4. Synthetic Data Generator for Training: Telegraf’s exec input can run a script that emits simulated sensor patterns. Posting those metrics to a non-production PI server through the Web API supplies realistic datasets for PI Vision training sessions without risking production tags.

Feedback

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