IBM AIX 7.2 – Common Problem 079 – 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

System slows or kills processes due to low paging space.

Environment & Reproduction

Occurs when workload grows past hd6 size or after memory leaks.

Root Cause Analysis

Active paging space usage exceeds npswarn/npskill thresholds.

Quick Triage

Check lsps -a and vmstat -v for paging high water marks.

Step-by-Step Diagnosis

Identify hogs with svmon -P -O summary=basic -u | head.

Solution – Primary Fix

Extend paging with chps -s 4 hd6 to add LPs; reboot not required.

Solution – Alternative Approaches

Alternative: mkps -a -n -s 4 rootvg to add a second paging space.

Verification & Acceptance Criteria

Verify lsps -s shows %Used dropping during a load test.

Rollback Plan

Reduce paging with rmps after a successful chps if oversized.

Prevention & Hardening

Tune vmo -p -o npswarn= and npskill= for early-warning behaviour.

Related Errors & Cross-Refs

Related: 0509-036 fork errors and SIGDANGER signals to processes.

Related tutorial: View the step-by-step tutorial for aix-7.2.

View all aix-7.2 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

IBM Docs: Paging space management and vmo tunable reference.