Cloudflare says a cache-transcoding prototype could materially expand effective CDN cache capacity by storing eligible assets in Zstandard-compressed form inside its Pingora-based edge stack.

In a September 1 engineering post, Cloudflare said the approach shrank eligible cached objects to roughly one-third of their original on-disk size in initial testing, while adding what it characterized as a small CPU cost on cache fill. The company said the tradeoff could create “petabytes of effective cache capacity” and reduce data transferred between Cloudflare data centers.

The idea is narrower than simply compressing every asset. Cloudflare said images, video and fonts are often already compressed, so the prototype focuses on compressible text such as HTML, JSON, CSS and JavaScript. In its traffic sample, those text formats represented 67.3% of requests and 22.3% of bytes, and about 71% of that text traffic arrived without a content-encoding header.

For hosting providers and site operators, the practical signal is that CDN economics are still being squeezed by storage and memory costs. Better internal cache density can help edge networks keep more origin content close to users, reduce origin revalidation pressure and limit inter-data-center transfer, even when site owners have not tuned compression at the origin.

Cloudflare described Cache Transcoding as a prototype rather than a customer-facing product launch. If it graduates into production, operators should still keep origin-side compression and cache headers in good shape: the CDN can optimize what it stores, but clear cacheability and content behavior remain the site owner’s job.

Source: Cloudflare Blog: “How we could save petabytes of cache storage with Zstandard and Pingora”.