Instance memory statistics

Job details

Parameters

Job Summary

• Purpose: The purpose of this job is to collect and monitor instance memory statistics in Oracle database systems.
• Why: Monitoring memory usage is crucial for database performance optimization. This job helps in identifying memory allocation issues and ensures efficient memory management, which is critical for maintaining system stability and performance.
• Manual checking: You can check instance memory statistics manually by querying various Oracle dynamic performance views directly:

select name, sum(bytes) as value from v$sgastat group by name;

Job Details

• Runtime Environment: The job is tailored for Oracle database instances where engine presence (“hasengine=‘YES’”) is mandatory.
• Category: Performance – This job is categorized under performance monitoring, focusing on instance memory metrics.
• Instance-specific: Yes – It is designed to collect data specific to each database instance, supporting multiple instances effectively.

Implementation

• Tables: The job involves creating several tables to store memory statistics history, current instance memory, historical aggregation of memory usage, and identifying names corresponding to memory statistics.
• Procedures:
• A procedure called `instance_memory_#instance~id#` is managed which collects, updates, and maintains memory statistic records.

Dependencies & Cleanup

• This job has several dependencies which include:
  • Data tables and views that must exist for collecting and aggregating stats.

• Clean-up actions are executed on failure to ensure environmental cleanliness and data integrity.

Reporting

• Report Template: The provided template generates detailed reports on instance memory statistics such as total size, buffer utilization, and free memory.
• Presentation Layers: Includes pie charts, tables, and category charts depicting memory utilization over time, initialization parameters, and SGA pool sizes.
• Select Queries: These are utilized within presentations to pull targeted data for reports, ensuring administrators receive comprehensible and relevant insights.

Conclusion

The monitoring job for dbWatch Control Center is a comprehensive task designed to provide deep insights into Oracle database memory usage. It supports database administrators by automating the collection and reporting of crucial performance metrics, aiding in proactive management and tuning of the database environment.