PHP：使用php-fpm时，何时应用.user.ini中的设置？

我在RHEL8系统上将Apache与php-fpm结合使用。 php-fpm是从 remi repo 安装的。

I'm using Apache with php-fpm on a RHEL8 system. php-fpm was installed from remi repo in version 7.2.

我添加了一个文件 .user.ini 在可访问网络的文件夹中，以设置 memory_limit = 256M （ /etc/php.ini的默认值为128M）。似乎有效。但是我发现，如果更改该值，似乎并不会立即应用该值并非总是。我通过反复调用输出 phpinfo（）; 的页面来进行检查。有时值会更改，有时则不会。

I've added a file .user.ini in a web accessible folder to set memory_limit=256M (default of /etc/php.ini is 128M). It seems to work. But I detected that the value does 'not always' seems to be applied immediately if I change it. I checked that by repeatedly calling a page that outputs phpinfo();. Sometimes the value is changed, sometimes not.

我想它是php-fpm及其进程池（如果我正确理解的话）。新流程将具有新价值。旧的珍惜旧的珍贵。如果页面被调用，您将永远不知道哪个进程真正响应。

I guess that it is php-fpm with its process pool (if I did understand that correctly). New processes will have the new value. Old values the old one. And if a page gets called, you never know which process actually responds.

我认为重新加载php-fmp（ systemctl重新加载php-fpm.service ）将重置这些进程，并且每个进程都具有更新后的值。

I think reloading php-fmp (systemctl reload php-fpm.service) resets those processes and each has the updated value.

有人可以解释它的工作原理吗？关于 .user.ini 和php-fpm的重要信息是什么？

Can anyone explain how it works exactly? What is important to know, about .user.ini and php-fpm? Can it be that some request will use the old value forever?