Dev image performance is 10x slower than prod
Description
I'm new to CraftCMS and inherited a website for maintanence. As the first step, I've tried to setup a dev and prod Docker environments. However, there seems to be a ~10x performance penalty when using craftcms/nginx:7.4-dev as base image compared to craftcms/nginx:7.4. I'm setting devMode: false.
I can see two problems:
- Everything is slower by a factor of ~10
- Rendering
_layouts/components/alertsseems to be the bottleneck
Using craftcms/nginx:7.4 (loading admin/dashboard takes under 500ms)
Using craftcms/nginx:7.4-dev (loading admin/dashboard takes under 5000ms)

Steps to reproduce
Additional info
- Craft version: Craft Pro 3.7.63.1
- PHP version: 7.4.33
- Database driver & version: MySQL 8.0.32
- Plugins & versions:
- Control Panel CSS 2.4.0
- Excerptify 1.0.1
- Freeform 3.13.22.1
- Mailchimp Subscribe 3.1.1.1
- Navigation 1.4.31
- Neo 2.13.16
- Opening Hours 1.0.0
- Redactor 2.10.11
- Redactor Custom Styles 3.0.4
- Redirect Manager 1.1.1
- SS Entry Importer 1.0.3
- Super Table 2.7.4
Not 100% sure, but this could be because PHP opcache is disabled for the dev environment.
We use the prod Docker image for development, and set this ENV PHP_OPCACHE_VALIDATE_TIMESTAMPS=1;. It still has opcache enabled, but it checks timestamps for changes in PHP files to clear te cache. Hope that also helps in your case.
I suspect @thijskaspers is right. It sounds like others have had luck with opcache enabled in dev, with opcache.validate_timestamps=1.
@thijskaspers any reservations about making this default for our dev image?
Related: https://github.com/craftcms/docker/issues/8
Thank you! Using prod image with ENV PHP_OPCACHE_VALIDATE_TIMESTAMPS=1 in the Dockerfile seems to work great.