IBM i Global

Introduction

Monitoring IBM i system performance doesn’t require deep technical expertise. IBM i provides built-in tools that allow users to check system health, track resource usage, and ensure smooth operations. This guide will introduce basic tools and techniques to monitor performance without needing advanced knowledge.

1. Understanding System Performance Metrics

Before diving into tools, it's helpful to know the key performance areas:

2. Tools for Monitoring IBM i Performance

IBM i provides several easy-to-use tools for performance monitoring.

a) Work with Active Jobs (WRKACTJOB)

This command helps you see which jobs are consuming resources.

• Type WRKACTJOB in the command line and press Enter.
• Look for:
• CPU % Usage: High values indicate heavy processing.
• Jobs in MSGW (Message Wait): These jobs may need attention.
• Run Priority: Lower numbers mean higher priority.

b) Work with System Status (WRKSYSSTS)

This tool provides an overview of system health.

• Type WRKSYSSTS and press Enter.
• Key areas to check:
• % CPU Used: If consistently high (90%+), performance may be impacted.
• Main Storage (Memory): Look for excessive paging.
• Jobs in System: Too many jobs can slow down performance.

c) Disk Usage (WRKDSKSTS)

Monitor disk space and activity.

• Type WRKDSKSTS and press Enter.
• Check for:
• Disk % Busy: High values (80%+) indicate potential bottlenecks.
• Disk Response Time: Slower response suggests issues.

d) Job Logs (DSPJOBLOG)

Check job logs to find errors or warnings.

• Type DSPJOBLOG and enter a job name.
• Look for error messages that need attention.

e) System Logs (DSPLOG)

Review overall system logs for warnings and errors.

• Type DSPLOG and set a date range to see recent events.

3. Simple Performance Optimization Tips

1. End Unused Jobs

• Use WRKACTJOB to find jobs consuming high CPU and end unnecessary ones:
• ENDJOB JOB(123456/QUSER/PROGRAM) OPTION(*IMMED)

2. Clear Old Spool Files

• Use WRKOUTQ to remove old print jobs that consume disk space.

3. Restart Long-Running Jobs

• Some jobs can run indefinitely, impacting performance. Check using WRKACTJOB and restart them if needed.

4. Monitor Disk Usage

• If disk usage is high, delete or archive old files to free space.

5. Schedule Regular Maintenance

• Use Job Scheduler (WRKJOBSCDE) to automate maintenance tasks.

4. When to Get Help from an Admin

While you can monitor performance easily, sometimes you may need assistance:

• If CPU stays above 90% for extended periods.
• If response times slow down significantly.
• If errors frequently appear in system logs.
• If storage usage reaches critical levels.

Conclusion

Monitoring IBM i system performance doesn’t require deep expertise. Using simple commands like WRKACTJOB, WRKSYSSTS, and WRKDSKSTS, you can track system health and take basic actions to optimize performance. Regular monitoring helps keep the system running smoothly, ensuring users experience minimal disruptions.