Troubleshooting guide
Troubleshooting Guide: WordPress High CPU Usage
Use this guide to work through the most likely causes, gather useful evidence and make production-safe changes without turning a small problem into a larger outage.
WordPresshigh CPUPHP-FPMMySQLCloudflare
What this problem usually means
WordPress high CPU can come from PHP execution, database load, bots, plugins, theme code, cron jobs, WordPress infrastructure actions, or cache misses. The fix is usually a combination of server-level checks and application-level cleanup.
Production caution: Installing more caching plugins without checking server logs can make diagnosis harder. Start by finding whether CPU is PHP, database, bots or background jobs.
Common symptoms
- CPU spikes during normal browsing
- Admin area is slow
- Checkout or cart pages hang
- Hosting account hits resource limits
- PHP-FPM or MySQL uses most CPU
Common causes
- No full-page cache or object cache where appropriate
- Heavy plugins or page builders
- wp-cron running too often
- Bot traffic hitting expensive endpoints
- Slow database queries and bloated tables
- WordPress infrastructure sessions, carts or checkout actions under load
Safe first checks
These checks are intended to assist identify the direction of the issue. Always adjust paths, solution names and commands for your environment.
Check top processes
top -o %CPUCheck PHP-FPM and web logs
tail -100 /var/log/nginx/access.log /var/log/nginx/error.logLook at WordPress cron
wp cron event list --due-now --path=/path/to/siteCheck database activity
mysqladmin processlistTypical fixes
- Identify heavy URLs and bot traffic in access logs
- Tune PHP-FPM workers to avoid overload
- Use Redis/object caching where useful
- Disable or reschedule expensive cron tasks
- Optimise database tables and slow queries
- Use Cloudflare or NGINX caching carefully for safe pages
When to get assist
Get assist if the system is production-facing, customer data is involved, backup processes are uncertain, or the issue affects revenue, security hardening or uptime. We can review the logs, confirm the cause and quote a fixed-scope fix where appropriate.
Need this fixed?
Get remote engineering help for this issue.
Fixed engineering help starts from $499. Emergency incident engineering assistance is $199/hr with a minimum window.