IBM AIX 7.1 – Common Problem 073 – Diagnosis and Fix

📖 ~1 min read

Table of contents

1. Symptom & Impact
2. Environment & Reproduction
3. Root Cause Analysis
4. Quick Triage
5. Step-by-Step Diagnosis
6. Solution – Primary Fix
7. Solution – Alternative Approaches
8. Verification & Acceptance Criteria
9. Rollback Plan
10. Prevention & Hardening
11. Related Errors & Cross-Refs
12. References & Further Reading

Symptom & Impact

WLM (Workload Manager) classes show CPU starvation on important class.

Environment & Reproduction

AIX 7.3 LPAR with multi-tenant workloads under WLM control.

Root Cause Analysis

Tier/shares assigned to gold class lower than expected after WLM update.

Quick Triage

Run wlmstat 5 and lsclass -a to view current allocation.

Step-by-Step Diagnosis

Use wlmstat -c 2 5 to confirm CPU% per class.

Solution – Primary Fix

Adjust class with chclass -c CPU=shares=200 -a tier=0 .

Solution – Alternative Approaches

Temporarily disable WLM with wlmcntrl -o to test app behaviour.

Verification & Acceptance Criteria

wlmstat shows target class receiving >=expected CPU share.

Rollback Plan

Restore previous class config with chclass from saved spec.

Prevention & Hardening

Version-control WLM class definitions and apply via SMIT.

Related Errors & Cross-Refs

WLM tier conflicts, unmanaged process drift.

Related tutorial: View the step-by-step tutorial for aix-7.1.

View all aix-7.1 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

AIX Workload Manager admin guide.