CentOS Stream 9 – Common Problem 237 – 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

OOM kills critical service randomly

Environment & Reproduction

Memory.high not set on slice while burst workloads run.

Root Cause Analysis

cgroup v2 memory pressure causes oom-kill on lowest-priority task.

Quick Triage

systemd-cgtop and journalctl -k | grep -i oom.

Step-by-Step Diagnosis

Run: systemctl status ; cat /sys/fs/cgroup//memory.current.

Solution – Primary Fix

Set MemoryHigh and MemoryMax in service drop-in: systemctl edit .

Solution – Alternative Approaches

Reserve memory with MemoryMin on critical units and reduce non-essential.

Verification & Acceptance Criteria

oom-kill counter stops incrementing and service stays running under burst.

Rollback Plan

Revert drop-in via systemctl revert and restart.

Prevention & Hardening

Define cgroup budgets in Ansible role with sane defaults per host class.

Automate patch management and compliance across your fleet with our DevOps services.

Related Errors & Cross-Refs

Pairs with Killed process and Out of memory journal entries.

Related tutorial: View the step-by-step tutorial for centos-stream-9.

View all centos-stream-9 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

systemd.resource-control(5) and cgroups v2 docs.