PostgreSQL Monitoring: System_health Alternatives in SQL Server

In PostgreSQL, the alternative to the SQL Server System_health Extended Event Session for monitoring and diagnosing system health is a combination of logging, extensions, and built-in tools. Here are some of the key components you can use:

1. Logging

PostgreSQL provides extensive logging capabilities that can be configured to capture various events and details about the database system.

Configuration: Adjust the postgresql.conf file to enable and configure logging.

  # Enable logging
  logging_collector = on

  # Set log file directory
  log_directory = 'pg_log'

  # Log file rotation settings
  log_rotation_age = 1d
  log_rotation_size = 10MB

  # Log level
  log_min_messages = notice
  log_min_error_statement = error
  log_min_duration_statement = 1000  # Log queries taking longer than 1 second

  # Log details
  log_statement = 'all'  # Log all statements
  log_checkpoints = on
  log_connections = on
  log_disconnections = on
  log_lock_waits = on
  log_temp_files = 0
  log_autovacuum_min_duration = 0

2. pg_stat_statements Extension

This extension provides a means to track execution statistics of all SQL statements executed by a server.

Installation: Enable the pg_stat_statements extension.
```
  CREATE EXTENSION pg_stat_statements;
```
Usage: Query the pg_stat_statements view to get statistics.
```
  SELECT * FROM pg_stat_statements;
```

3. pgBadger

pgBadger is a fast PostgreSQL log analyzer that generates detailed reports and insights from PostgreSQL log files.

Installation and Usage: Download and install pgBadger from the official website. Use it to analyze log files.
```
  pgbadger /path/to/your/logfile
```

4. pg_stat_activity View

The pg_stat_activity view shows information about the current activity in the database, including active queries, their duration, and state.

Usage: Query the pg_stat_activity view.
```
  SELECT * FROM pg_stat_activity;
```

5. pgAdmin or Other Monitoring Tools

pgAdmin and other third-party tools like Datadog, New Relic, and Zabbix provide comprehensive monitoring and alerting capabilities.

6. PostgreSQL Monitoring Extensions

Several extensions can be used for more advanced monitoring:

pg_stat_monitor: A more detailed and fine-grained statistics collection extension.
```
  CREATE EXTENSION pg_stat_monitor;
  SELECT * FROM pg_stat_monitor;
```
pg_prometheus: Integrates PostgreSQL metrics with Prometheus for advanced monitoring and alerting.

7. Automated Alerts and Health Checks

Implement automated scripts or tools to periodically check system health and send alerts based on specific conditions or thresholds.

Summary

While PostgreSQL does not have a direct equivalent to SQL Server's System_health Extended Event Session, it offers a rich set of tools and extensions for monitoring and diagnostics. By combining logging, pg_stat_statements, pg_stat_activity, pgBadger, and other extensions, you can achieve comprehensive monitoring and health checks for your PostgreSQL database.

More PostgreSQL Blogs to read

PostgreSQL Monitoring and Diagnostics: Alternatives to SQL Server System_health

PostgreSQL Diagnostics: Key Alternatives to SQL Server System_health