Akamai Server-Timing

RUMvision can collect Akamai timing data when your website exposes it through the Server-Timing response header.

This helps you understand whether slow server response times are caused by Akamai edge processing, your origin server, or cache behavior.

If your site is not exposing these headers yet, you can enable or configure them in Akamai for your property.

Add Server-Timing via Akamai

Below are the recommended fields to expose. Once these fields are exposed and Akamai is selected as the CDN in your tech stack settings and enabled the Akamai checkbox, we will automatically collect them.

ValueSourceMeaning
cdn-cacheAkamai CDN metricShows whether the response was served from cache, for example HIT or MISS.
edgeAkamai CDN metricTime spent processing the request at the Akamai edge.
originAkamai CDN metricTime spent waiting for the origin. This is only relevant when Akamai had to contact the origin.

Where to implement

In Akamai, this is usually configured at property level.

  • Akamai Control Center
  • Property Manager
  • Select property
  • Configure Server-Timing / CDN edge metrics

The exact setup can depend on your Akamai contract, property configuration, and enabled behaviors. If you do not see an option for Server-Timing or CDN edge metrics, ask your Akamai administrator or Akamai support to enable these metrics for your property.

Rule to implement

Enable Akamai Server-Timing metrics for all HTML document requests. These are the main page requests RUMvision uses to understand document TTFB and backend-related delays.

This usually means the main document request of your pages, not images, scripts, stylesheets, or API calls.

If needed, you can also expose these timings on other request types, but HTML document requests are the recommended starting point.

The response should expose these Server-Timing values:

MetricExpected format
Cache statuscdn-cache;desc=HIT or cdn-cache;desc=MISS
Edge timeedge;dur=12
Origin timeorigin;dur=248

Testing the outcome

Next step is testing the outcome. You could either wait for data to arrive in your RUMvision dashboard, or proactively test the outcome using the DevTools of your preferred browser.

Expected outcome

After enabling the metrics, your HTML document should return a Server-Timing header similar to this:

Server-Timing: cdn-cache;desc=MISS, edge;dur=12, origin;dur=248

For a cached response, origin may be missing or 0, because Akamai did not need to contact the origin server.

Server-Timing: cdn-cache;desc=HIT, edge;dur=8, origin;dur=0

Check the response headers

To verify the setup:

  1. Open your website in Chrome or Edge.
  2. Open DevTools.
  3. Go to the Network tab.
  4. Reload the page.
  5. Click the main HTML document request.
  6. Check the Response Headers section.
  7. Look for server-timing.

Test in DevTools Console

As the browser exposes Server-Timing values through the PerformanceServerTiming interface, you can also test it in the browser console by running the following JavaScript:

const navEntries = window.performance.getEntriesByType('navigation');
console.table( navEntries[0].serverTiming );

Important

In general, be sure to:

  • Always test on staging environment before deploying these steps to a production environment.
  • Avoid exposing sensitive internal details. Server-Timing data is visible in the browser, so only expose metrics that are safe to share with visitors and third-party scripts.

Akamai notes

Akamai setup can be property-specific. If you do not see these values after enabling them, check whether the behavior is applied to your production property and whether it applies to HTML document requests.

If your origin already sends a Server-Timing header, make sure the Akamai configuration does not remove or overwrite useful existing metrics.

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