Use of PIDFile= in php-fpm.service

Description

When using Type=simple or Type=notify services, the process executed in ExecStart= is monitored directly by systemd and is automatically the main PID. The use of PIDFile= is useless and discouraged by the systemd.service(5) manual page:

Note that PID files should be avoided in modern projects. Use Type=notify, Type=notify-reload or Type=simple where possible, which does not require use of PID files to determine the main process of a service and avoids needless forking.

Source: https://www.freedesktop.org/software/systemd/man/latest/systemd.service.html#PIDFile=

Furthermore, the default configuration of php-fpm.conf has pid = commented out, which is equivalent to not having a PID file.

From systemd's point of view, the service remains exactly the same without the PIDFile= directive. I suggest, therefore, that it be dropped.

PHP Version

PHP 8.5.5 (cli) (built: Apr  8 2026 14:36:19) (NTS)
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Operating System

No response

Start by locating the php-fpm.service unit and read its PIDFile= setting alongside the default php-fpm.conf, where pid = is commented out. Review the systemd.service(5) guidance linked in the issue, then verify that removing the directive leaves the service definition unchanged in behavior and that the unit no longer contains PIDFile=.