The goal of the beta cluster is to "provide an exact copy of the WMF production cluster (including db hosts, apaches, logging, squids, varnish caching, image scalers, etc.) using Wikimedia Labs instances". In the case of image scalers, it really falls short of this goal though; the setup is not even remotely similar:
- prod is using swift to store the files, beta uses NFS - T64835
- deployment-upload is not puppetized at all (according to the beta config overview page) so there are probably all sorts of differences in installed packages.
- prod uses custom Varnish code to redirect thumbnail misses to Swift and then to the scalers (according to (1)), beta uses nginx with a 404 handler php script which is as far as I can tell not tracked in git and seems to be a modified version of a several years old revision of MediaWiki's thumb.php
prod uses standalone image scaler servers, on beta image scaling seems to be done by the standard apache backends (swift has thumbhost set to the text cache's internal IP)Obsolete per T187899.
... and probably more, given that the beta file server was set up a long time ago, and not maintained since.