2 / 4 CDN & Edge Caching

Two Hundred Hungry Edges

Your CDN has roughly 200 POPs and you set a 60 second TTL on a popular API response. Origin logs show a steady drumbeat of about 200 fetches per minute for that one URL even though it is cacheable. What is happening, and what is the standard remedy?

A

The origin is being health-checked once per POP per minute, so lowering the health check frequency removes the load

B

Each POP caches independently and refetches on expiry, so an origin shield (a shared parent cache) collapses them into one

C

The POPs are gossiping cache state between themselves, so disabling peer replication removes the redundant origin fetches

D

The TTL is ignored because the response carries no ETag, so adding a strong validator will stop the repeated refetches