🧠 Symptoms
Your websites are loading slowly or failing to load, especially under traffic spikes. Errors may appear in your logs:
Apache error_log / stderr.log:
Reached max children process limit: 10, extra: 30, current: 40, busy: 40, please increase LSAPI_CHILDREN.
connection to [uds://tmp/lshttpd/APVH_example-php74.sock]... error: Resource temporarily unavailable!This error indicates the PHP process limit has been reached. LiteSpeed’s PHP suEXEC Max Conn setting (and its LSAPI_CHILDREN environment variable) needs to be increased.
🛠️ Cause
LiteSpeed limits the number of PHP processes per user to conserve resources. When this limit is exceeded, additional requests are delayed or fail.
✅ Resolution: Increase LSAPI_CHILDREN Limit
1. Access WHM as root
Log in to WHM using the root account.
2. Go to LiteSpeed Web Server Plugin
- WHM Menu:
Home » Plugins » LiteSpeed Web Server Plugin
3. Launch the WebAdmin Console
- Click “LiteSpeed Configuration”
- Click “WebAdmin Console” (opens in a new window/tab)
4. Navigate to PHP Handler Settings
- Click the Configuration icon (top menu)
- Go to the “PHP” tab
- In “PHP Handler Defaults”, click Edit
5. Modify LSAPI_CHILDREN
- Scroll to the Environment section
- Locate the entry like:
PHP_LSAPI_CHILDREN=10 - Increase the value. Suggested values:
- Low traffic:
20 - Medium traffic:
40 - High traffic:
60+(depending on server RAM/CPU)
- Low traffic:
⚠️ Don’t set it too high. Monitor your server’s RAM/CPU usage to avoid overloading.
6. Save and Restart
- Click Save
- At the top of the page, click “Graceful Restart” to apply the changes
📌 Optional: Tune PHP suEXEC Max Conn
For even better control, also adjust this in WHM:
- WHM → Service Configuration → Apache Configuration → PHP and SuExec Configuration
- Modify PHP suEXEC Max Conn value per PHP version or user pool
- Default: 10
Recommended: 30–50 depending on load
📁 Additional Resources
- LiteSpeed LSAPI Configuration Guide
- WHM Apache Configuration Documentation