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.

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!

[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