Sites slow or not loading: please increase LSAPI_CHILDREN

Symptoms

Some sites load slowly or do not load, and errors similar to the following can be seen in Apache's error_log and stderr.log logs, respectively.

CONFIG_TEXT: 2022-02-08 16:27:52.002950 [INFO] [26969] [T0] [203.0.113.2:38788#APVH_domain.tld] connection to [uds://tmp/lshttpd/APVH_eema_Suea-php74.sock] on request #0, confirmed, 0, associated process: 0, running: 0, error: Resource temporarily unavailable!

CONFIG_TEXT: [UID:2355][254905] Reached max children process limit: 10, extra: 30, current: 40, busy: 40, please increase LSAPI_CHILDREN.

Description

This issue occurs when a domain hits LiteSpeed's max children process limit. LiteSpeed's "PHP suEXEC Max Conn" setting must be increased to address this issue.

Workaround

1. Log into WHM as the root user.
2. Navigate to Home / Plugins / LiteSpeed Web Server Plugin.
3. Click LiteSpeed Configuration.
4. Open and log into the WebAdmin Console.
5. Click the "Configuration icon.
6. Select the "PHP tab.
7. Find the "PHP Handler Defaults section and click the Edit button.
8. In the Environment section, find the PHP_LSAPI_CHILDREN= definition and raise the value.
9. Click Save.
10. Click Graceful Restart at the top of the page.

Additional resources

LSPHP Options

Tuning: PHP suEXEC Max Conn