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

首先定位 php-fpm.service 单元，并结合默认的 php-fpm.conf 读取其中的 PIDFile= 设置；在该文件中，pid = 被注释掉了。查看 issue 中链接的 systemd.service(5) 指南，然后验证移除该指令不会改变服务定义的行为，并且该单元不再包含 PIDFile=。