Caching is a magic trick. Instead of a customer’s origin responding to every request, Cloudflare’s 200+ data centers around the world respond with content that is cached geographically close to visitors. This dramatically improves the load performance for web pages while decreasing the bandwidth costs by having Cloudflare respond to a request with cached content.
However, if content is not in cache, Cloudflare data centers must contact the origin server to receive the content. This isn’t as fast as delivering content from cache. It also places load on an origin server, and is more costly compared to serving directly from cache. These issues can be amplified depending on the geographic distribution of a website’s visitors, the number of data centers contacting the origin, and the available origin resources for responding to requests.
To decrease the number of times our network of data centers communicate with an origin, we organize data centers into tiers so that only upper-tier data centers can request content from an origin and then they spread content to lower tiers. This means content that loads faster for visitors, is cheaper to serve, and reduces origin resource consumption.
Today, I’m thrilled to announce a fundamental improvement to Argo Tiered Cache we’re calling Smart Tiered Cache Topology. When enabled, Argo Tiered Cache will now dynamically select the single best upper tier for each of your website’s origins while providing tiered cache analytics showing how your custom topology is performing.
Smarter Tiered Cache Topology Generation
Tiered Cache is part of Argo, a constellation of products that analyzes and optimizes routing decisions across the global Internet in real-time by processing information from every Cloudflare request to determine which routes to an origin are fast, which are slow, and what the optimum path from visitor to content is at any given moment. Previously, Argo Tiered Cache would use a static collection of upper-tier data centers to communicate with the origin. With the improvements we’re announcing today, Tiered Cache can now dynamically find the single best upper tier for an origin using Argo performance and routing data. When Argo is enabled and a request for particular content is made, we collect latency data for each request to pick the optimal path. Using this latency data, we can determine how well any upper-tier data center is connected with an origin and can empirically select the best data center with the lowest latency to be the upper tier for an origin.
Argo Tiered Cache
Taking one step back, tiered caching is a practice where Cloudflare’s network of global data centers are subdivided into a hierarchy of upper tiers and lower tiers. In order to control bandwidth and number of connections between an origin and Cloudflare, only upper tiers are permitted to request content from an origin and must propagate that information to the lower tiers. In this way, Cloudflare data centers first talk to each other to find content before asking the origin. This practice improves bandwidth efficiency by limiting the number of data centers that can ask the origin for content, reduces origin load, and makes websites more cost-effective to operate. Argo Tiered Cache customers only pay for data transfer between the client and edge, and we take care of the rest. Tiered caching also allows for improved performance for visitors, because distances and links traversed between Cloudflare data centers are generally shorter and faster than the links between data centers and origins.
Previously, when Argo Tiered Cache was enabled for a website, several of Cloudflare’s largest and most-connected data centers were determined to be upper tiers and could pull content from an origin on a cache MISS. While utilizing a topology consisting of numerous upper-tier data centers may be globally performant, we found that cost-sensitive customers generally wanted to find the single best upper tier for their origin to ensure efficient data transfer of their content to Cloudflare’s network. We built Smart Tiered Cache Topology for this reason.
How to enable Smart Tiered Cache Topology
When you enable Argo Tiered Cache, Cloudflare now by default concentrates connections to origin servers so they come from a single data center. This is done without needing to work with our Customer Success or Solutions Engineering organization to custom configure the best single upper tier. Argo customers can generate this topology by:
Logging into your Cloudflare account.
Navigating to the Traffic tab in the dashboard.
Ensuring you have Argo enabled.
From there, Non-Enterprise Argo customers will automatically be enrolled in Smart Tiered Cache Topology without needing to make any additional changes.
Enterprise customers can select the type of topology they’d like to generate.
Self-serve Argo customers are automatically enrolled in Smart Tiered Cache Topology
Enterprise customers can determine the tiered cache topology that works best for them.
More data, fewer problems
Once enabled, in addition to performance and cost improvements, Smart Tiered Cache Topology also delivers summary analytics for how the upper tiers are performing so that you can monitor the cost and performance benefits your website is receiving. These analytics are available in the Cache Tab of the dashboard in the Tiered Cache section. The “Primary Data Center” and “Secondary Data Center” fields show you which data centers were determined to be the best upper tier and failover for your origin. “Cached Hits” and the “Hit Ratio” shows you the proportion of requests that were served by the upper tier and how many needed to be forwarded on to the origin for a response. “Bytes Saved” indicates the total transfer from the upper-tier data center to the lower tiers, showing the total bandwidth saved by having Cloudflare’s lower tier data centers ask the upper tiers for the content instead of the origin.
Smart Tiered Cache Topology works with Cloudflare’s existing products to deliver you a seamless, easy, and performant experience that saves you money and provides you useful information about how your upper tiers are working with your origins. Smart Tiered Cache Topology stands on the shoulders of some of the most resilient and useful products at Cloudflare to provide even more benefits to webmasters.
If you’re interested in seeing how Argo and Smart Tiered Cache Topology can benefit your web property, please login to your Cloudflare account and find more information in the Traffic tab of the dashboard here.