Overview

A Pod that feels slow, or that is consistently pegged at 100% CPU or out of memory, needs investigation before it affects your users. This article shows how to find the culprit.

Before you begin

• Root or sudo access.
• Note what changed recently — a new deployment, a traffic spike, or a new plugin.

Steps

1. Get a quick overview with top or htop:

bash top

Press M to sort by memory or P by CPU.

1. Find the heaviest processes non-interactively:

bash ps aux --sort=-%cpu | head ps aux --sort=-%mem | head

1. Check memory and swap:

bash free -h

If swap is heavily used and available memory is near zero, you are memory-constrained.

1. Check load average and CPU count:

bash uptime nproc

A load average higher than your CPU count means processes are queueing.

1. Investigate the top process. For example, for a web service:

bash systemctl status nginx journalctl -u php8.2-fpm --since "1 hour ago"

For a database, look at slow queries rather than assuming the database is at fault.

1. Look for runaways or malware. Unexpected processes consuming CPU (especially miners) are a red flag:

bash sudo ps aux | grep -v '\[' sudo ss -tp

1. Reduce pressure. Common fixes:
   • Tune the number of PHP-FPM or worker processes.
   • Enable caching (OPcache, Redis) for web applications.
   • Reschedule heavy cron jobs to off-peak times.
   • Add swap space as a safety net.
2. Upgrade if it is genuine demand. If the workload has simply outgrown the Pod, resize to a larger CPU Pod from the ALYPOD Console.

Troubleshooting

• Problem: CPU is high but the top process keeps changing. Solution: Use pidstat 1 or atop to see which processes spike over time.
• Problem: The OOM killer is terminating services. Solution: Check dmesg | grep -i oom, increase memory, or fix the leak; add swap as a temporary buffer.

Related articles

• [Disk is full: how to free space]
• [My website shows a 500 error]
• [Protecting your server against malware]