Upload.wikimedia.org
From Wikitech
Caching layer
Backend: storage
Backend: scaling
[3:33pm] mark: 01:31:52 <TimStarling> the first is for thumb.php requests by users, the second is for ordinary requests via the 404 handler [3:34pm] mark: so it's accessed in two ways [3:34pm] mark: one via squid directly
please add more documentation thx
