ERROR: unable to read what child 15029 said into stderr: Bad file descriptor (9)

[njaciklum]

Description

We recently upgraded our application, which is built using CodeIgniter 3, from PHP 8.0 to 8.2. However, we've been encountering persistent errors in our logs that didn't occur with PHP 8.0.

The error message is as follows:

ERROR: unable to read what child 15029 said into stderr: Bad file descriptor (9)

We have attempted to address this issue by modifying the following configuration values in our PHP-FPM configuration, but with no success:

• pm.max_children = 100
• pm.process_idle_timeout = 1800
• pm.max_requests = 400
• Increased max resources

We have tried increasing our ECS instance size with no luck.

Real-time PHP-FPM Status

Any help in this regard would be greatly appreciated

PHP Version

PHP 8.2.x

Operating System

Debian 12

[bukka]

My guess is that it's happening because child gets killed and pipe is closed on the child side so master gets this error which it logs. The pm.max_requests is very low which means that PHP will kill child after that amount of requests. This looks pretty similar to #11707 where the OP saw similar issue after the update too. I would recommend trying to significantly increase pm.max_requests first and see if it helps.

[njaciklum]

Appreciate it, @bukka! Unlike blackwolf12333, we can confirm that configurations haven't been updated in years.

For now, we've set max_requests = 0 and are monitoring it closely. Will share any further updates as soon we have them.

[njaciklum]

Thanks for referring to the post @bukka

Just an update, we haven't observed the issue since we updated the configurations

pm.max_children = 300
pm. start_servers = 50
pm. min_spare_servers = 30
pm. max_spare_servers = 50
pm. max_requests = 0

Continuing to monitor the logs for a few more days.

[njaciklum]

After observing the logs for couple of weeks, no new log has been found related to this issue, closing this issue now.