The marketplace that purged its whole CDN to fix one price

The marketplace that purged its whole CDN to fix one price

A vintage-furniture marketplace updated prices hourly. Their deploy script ran a full cache purge each time — wiping 9 million edge objects to change maybe 200 of them. After every purge, cache-hit ratio cratered to near zero, origin got hammered for 20 minutes, and São Paulo users felt every cold fetch.

We tagged each product page at the edge with a surrogate key like product-58213. The price-update job now purges only the keys that changed.

A pricing run that used to evict 9M objects now evicts ~200. Post-deploy cache-hit ratio stayed at 96% instead of falling to 4%. Origin load during updates dropped roughly 95%, and the São Paulo cold-fetch spike vanished entirely.

The number that mattered: 9,000,000 objects purged down to 200.