About the stats for Deliver services

The Stats page for Deliver services allows you to monitor your real-time analytics and view your historical caching statistics for your services on the web interface.

Before you begin

Be sure you know how to access the web interface controls and pay specific attention to basic information about the Stats interface before learning about the Deliver service specifics you'll encounter here.

Viewing the Real-time stats

The Real-time stats graphs allow you to separately monitor caching for your services in real time, as they operate on a second-by-second basis.

In addition to a menu allowing you to select the specific data center from which to view data (it defaults to data from all data centers), the top of the dashboard includes the following real-time cache activity:

• Requests: the number of requests Fastly receives for your site per second.
• Hits: the number of times requested data is found in cache and does not require making a fetch your origin server.
• Misses: the number of times requested data is not found in cache and has to be requested from your origin server.
• Hit Ratio: the percentage of content being accessed that is currently cached by Fastly. Also known as Fastly's definition of cache hit ratio. While there are many ways to calculate cache hit ratio, at Fastly this is defined as the proportion of cache hits (hits) to all cacheable content (hits + misses). If shielding is enabled, it can cause the hit ratio to be inaccurate.
• Errors: the number of error responses per second that occur as Fastly receives requests for your site.
• Hit Time: the average amount of time (in milliseconds) spent processing cache hits.
• Miss Time: the average amount of time (in milliseconds) spent processing cache misses.

Below the real-time cache activity summary data, several graphs appear:

The graphed cache activity includes:

• Global POP Traffic: a heat map displaying global POP traffic through all POPs for your service.
• Requests: a graph displaying the total number of requests received for your site by Fastly over time.
• Errors: a graph displaying the number of error requests that occurred over time.
• Hit Ratio: a graph displaying the percentage of content being accessed that is currently cached by Fastly over time.
• Bandwidth: a graph displaying the bandwidth served from Fastly's servers to your website's visitors.
• Image Optimizer: when enabled, a graph displaying the number of responses that came from the Fastly Image Optimizer service over time.
• Image Optimizer (Videos): when enabled, a graph displaying the number of videos responses that came from the Fastly Image Optimizer.
• Image Optimizer (Video Frames): when enabled, a graph displaying the number of video frames that came from the Fastly Image Optimizer. A video frame is an individual image in a sequence of images that make up a video.
• Logs: a graph displaying the number of logs sent to your endpoints from Fastly.
• Log Bandwidth: a graph displaying the total bandwidth size of the logs sent to your endpoints from Fastly.
• Origin Latency: a histogram displaying the average amount of time to first byte (measured in milliseconds) on a cache miss or pass. High origin latency means that your backends are taking longer to process requests.

If you've just created your service, you might see a message saying there's nothing to see yet. This might be because:

• Not enough data is going to your site. If this is the case, visit the site yourself to trigger some traffic.
• You've made a CNAME change. If this is the case, it could take from a few minutes to hours for the change to propagate your DNS servers. See how to edit your DNS record to point to Fastly for more information.

Once you start seeing real-time cache activity, you also can interact with your stats graphs.

Viewing the Historic stats

The Historic stats graphs provide a visual interface to our stats API for a selected Fastly service. You can also display historical metrics aggregated across all your Fastly services by clicking All services. The graphs display metrics derived from your site's statistical information. If you've just created your service, you might see a message saying there's nothing to see yet.

The displayed caching and performance metrics help you optimize your website's speed. These metrics include the following:

• Hit Ratio metrics tell you how well you are caching content using Fastly. This metric represents the proportion of cache hits (hits) to all cacheable content (hits + misses). Increasing your hit ratio improves the overall performance benefit of using Fastly.
• Cache Coverage metrics show how much of your site you are caching with Fastly. This metric represents the ratio of cacheable requests (i.e., non "pass" requests) to total requests. Improving your cache coverage by reducing passes can improve site performance and reduce load on your origin servers.
• Caching Overview metrics compare Cache Hits, Cache Misses, Synthetic Responses (in VCL edge responses), and Passes (or requests that cannot be cached according to your configuration).

The traffic metrics analyze your website's traffic as it evolves over time. These metrics include the following:

• Requests metrics show you the total number of requests that were received for your site by Fastly.
• Bytes Transferred metrics show you the total number of bytes transferred by Fastly for your service.
• Header & Body Bytes Transferred metrics show you the relative values of bytes transferred when serving the body portion of HTTP requests and the header portion of the requests.
• Miss Latency metrics show the distribution of only the miss latency times for your origin.
• Error Ratio metrics show you the ratio of error responses (4xx and 5XX status code errors) compared to the total number of requests for your site. This metric allows you to filter types of error responses and quickly identify error spikes at given times.
• HTTP Info, Success, & Redirects metrics show the number of HTTP Info (1XX), Success (2XX), and Redirect (3XX) statuses served for your site using Fastly.
• Status 3XX Details metrics show the breakdown between the number of HTTP Status 301s, 302s, 304s, and other 3XX requests.
• HTTP Client and Server Errors metrics show the number of HTTP Client Errors (4XX), and Server Errors (5XX) served for your site by Fastly.
• HTTP versions metrics show the number of requests using HTTP/1.1, HTTP/2, and HTTP/3 (QUIC) protocols.
• TLS versions metrics show the number of requests using TLS 1.0, TLS 1.1, TLS 1.2, and TLS 1.3 protocols.
• Logs metrics show the number of logs sent to your endpoints from Fastly.
• Log Bandwidth metrics show the total bandwidth size of the logs sent to your endpoints from Fastly.
• When enabled, Image Optimization Requests metrics show you the number of responses that came from the Fastly Image Optimization service.

What's next

Once you start to see your caching and performance metrics, you also can interact with your stats graphs.