No file is created in the assigned multiprocess directory

I've been trying to use multiprocessing mode but I'm struggling to make it work properly.
Even though I set the multiprocess directory, no metric writes any files. I've checked for permissions for writing in the directory and they exist.
I'm currently trying to work with a Gauge in the livesum mode. The metric is incrementing properly within the application but no updates are made available to Prometheus. Is anything else other than setting the directory and a multiprocess mode for the Gauge needed that I might be missing?
I'm using Prometheus inside a Docker container with the port forwarding.

首先使用已配置的多进程目录，在 livesum 模式下重现报告的 Gauge，然后检查 issue 中描述的多进程设置以及 Docker 到 Prometheus 的连接。完成标准是确定为什么没有出现指标文件或 Prometheus 更新，并记录可复现的修复方法或缺失的配置。