IBM AIX 7.3 – Common Problem 020 – 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

Java applications dump core with SIGSEGV after JRE service refresh.

Environment & Reproduction

IBM AIX 7.3 LPAR exhibiting Java / JRE crash on AIX issues under standard PowerVM workloads.

lslpp -L Java*
ulimit -a

Root Cause Analysis

AIX JIT incompatibility with code path or insufficient maxdata/datasize ulimit.

Quick Triage

Confirm scope with errpt, recent changes, and subsystem state via lssrc.

ulimit -a
lslpp -L Java8_64.sdk

Step-by-Step Diagnosis

Inspect javacore and AIX core file with snapcore.

snapcore -d /tmp core java
sdiff javacore* | head

Solution – Primary Fix

Set LDR_CNTRL=MAXDATA and disable JIT for the failing module.

export LDR_CNTRL=MAXDATA=0x80000000
export JAVA_OPTS='-Xjit:exclude={com/x/Y.method}'

Solution – Alternative Approaches

Roll back JRE fileset to previous service refresh.

Verification & Acceptance Criteria

Confirm subsystem returns to RUNNING state and errpt shows no new entries.

java -version
lslpp -L Java8_64.sdk

Rollback Plan

Restore prior configuration from mksysb or alt_disk_install clone if the fix regresses.

installp -u Java8_64.sdk

Prevention & Hardening

Encode the fix in NIM customisation scripts and monitor via topas/nmon.

smit installp  # pin JRE level via NIM

Related Errors & Cross-Refs

javacore.* SIGSEGV; JIT exclude filters

Related tutorial: View the step-by-step tutorial for aix-7.3.

View all aix-7.3 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

IBM SDK for AIX troubleshooting