Measure cache offload for a domain

Filter Real-Time Metrics to one domain and read how much of its data and requests came from cache, in Azion Console or with the GraphQL API.

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You can measure how much of one domain’s traffic your applications serve from cache with Real-Time Metrics, in Azion Console or with the GraphQL API.

Three measures answer the question. Offload is the share of data or requests that the data center delivered from its cache. Saved counts the data or requests it delivered from cache, without fetching the content from the origin. Missed counts what it delivered after fetching the content from the origin. For the full definition of each chart, refer to Build dashboards.

The examples read the last 24 hours of the host www.example.com. Replace it with a domain your workload answers on.

Select your interface once. The prerequisites and every task below show only that path.

Prerequisites

Filter to the domain

With no filter, the cache charts cover every application of the account. A filter on the host keeps only the requests to that domain.

In the API, the hostEq filter keeps the requests of one host, next to the tsRange filter that sets the period. Before you read the cache values, confirm that the host has requests in the range.

Send a POST request to https://api.azion.com/v4/metrics/graphql. Replace [TOKEN VALUE] with your personal token, and the host and dates with your own:

Shell
01curl -X POST 'https://api.azion.com/v4/metrics/graphql' \
02 -H 'Content-Type: application/json' \
03 -H 'Authorization: Token [TOKEN VALUE]' \
04 -d '{"query":"query RequestsForHost($begin: DateTime!, $end: DateTime!) { httpMetrics(limit: 1, filter: { tsRange: { begin: $begin, end: $end }, hostEq: \"www.example.com\" }) { requestsTotal } }","variables":{"begin":"2026-01-01T12:00:00","end":"2026-01-02T12:00:00"}}'

The API answers 200 with the request count of the host:

JSON
01{
02 "data": {
03 "httpMetrics": [
04 {
05 "requestsTotal": 982
06 }
07 ]
08 }
09}

requestsTotal counts the requests to the host in the range. A requestsTotal of 0 means no request to that host reached your applications in the range. Correct the host or the dates before you read the cache values.

To filter the dashboards to one domain in Azion Console:

Open Real-Time Metrics

Access Azion Console > Real-Time Metrics.

The page opens on the Build category, the Applications tab, and the Data Transferred dashboard.

Select Last 24 hours

In the time-range picker, in the Quick tab, under Commonly used, select Last 24 hours.

Select Update
Add a filter

In the filter row, select the filter icon, whose tooltip reads Add filter.

Select the Host field

In Filter, select Host.

Select the Equals operator

In Operator, select Equals.

Enter the domain

Enter www.example.com as the value.

Select Apply

A chip under the filter row reads Host equals: www.example.com. Every chart of Data Transferred now shows only the requests to that domain, over the last 24 hours.

To keep every domain of one workload instead, select the Domain field, labeled Workload on some accounts, and select the workload from its list.

Read the offload of data and requests

Real-Time Metrics measures the cache in two units. The Data Transferred dashboard counts bytes, and the Requests dashboard counts requests.

To read the same values with the API, select the cache fields of the httpMetrics dataset with the same filter:

Shell
01curl -X POST 'https://api.azion.com/v4/metrics/graphql' \
02 -H 'Content-Type: application/json' \
03 -H 'Authorization: Token [TOKEN VALUE]' \
04 -d '{"query":"query CacheOffloadForHost($begin: DateTime!, $end: DateTime!) { httpMetrics(limit: 1, filter: { tsRange: { begin: $begin, end: $end }, hostEq: \"www.example.com\" }) { requestsTotal requestsOffloaded savedRequests missedRequests dataTransferredTotal offload savedData missedData bandwidthOffload } }","variables":{"begin":"2026-01-01T12:00:00","end":"2026-01-02T12:00:00"}}'

The API answers 200 with one row for the host:

JSON
01{
02 "data": {
03 "httpMetrics": [
04 {
05 "requestsTotal": 982,
06 "requestsOffloaded": 5.19,
07 "savedRequests": 51.0,
08 "missedRequests": 931.0,
09 "dataTransferredTotal": 114490585.0,
10 "offload": 0.51,
11 "savedData": 577373.0,
12 "missedData": 113387464.0,
13 "bandwidthOffload": 0.51
14 }
15 ]
16 }
17}

The row covers the whole range. Read the fields as follows:

  • requestsOffloaded is the percentage of requests served from cache: savedRequests divided by requestsTotal.
  • offload is the percentage of data served from cache: savedData divided by the sum of savedData and missedData.
  • bandwidthOffload is the same share, measured on bandwidth.
  • savedData and missedData are in bytes.

savedRequests and missedRequests add up to requestsTotal. For every field of the dataset, refer to Real-Time Metrics GraphQL fields.

To read the offload of the domain in Azion Console, with the host filter applied:

Read the data offload

On the Data Transferred dashboard, find the Offload entry in the legend of the Edge Offload chart.

Read the saved and missed data

In the legends of the Saved Data and Missed Data charts, find the byte totals of the range.

Select Requests in the dashboard selector
Read the request offload

In the Requests Offloaded chart, find the Requests Offloaded entry in the legend.

Read the saved and missed requests

In the legends of the Saved Requests and Missed Requests charts, find the request totals of the range.

The host filter stays applied on Requests. Both dashboards read the httpMetrics dataset, and only a switch to a dashboard that reads another dataset clears the filters.

The aggregation tag of Edge Offload and Requests Offloaded reads Average. Their legends show the average of the chart’s points, not the share over the whole range. For the share of data over the whole range, divide the Saved Data total by the sum of the Saved Data and Missed Data totals.

Find what reached the origin

Missed data and missed requests are the content the data center fetched from your origin before it delivered it. The higher they are, the more of the domain’s demand your origin handles. When the application uses Tiered Cache, the Tiered Cache Offload chart of the Tiered Cache tab shows the share of data that the Tiered Cache layer delivered to the data center without fetching it from the origin.

To see how the requests of the host split by cache status, group them by upstreamCacheStatus, the status of the local cache for each request. The query sums requests for each status, the largest first:

Shell
01curl -X POST 'https://api.azion.com/v4/metrics/graphql' \
02 -H 'Content-Type: application/json' \
03 -H 'Authorization: Token [TOKEN VALUE]' \
04 -d '{"query":"query RequestsByCacheStatus($begin: DateTime!, $end: DateTime!) { httpMetrics(limit: 20, filter: { tsRange: { begin: $begin, end: $end }, hostEq: \"www.example.com\" }, aggregate: { sum: requests }, groupBy: [upstreamCacheStatus], orderBy: [sum_DESC]) { upstreamCacheStatus sum } }","variables":{"begin":"2026-01-01T12:00:00","end":"2026-01-02T12:00:00"}}'

The API answers 200 with one row for each cache status:

JSON
01{
02 "data": {
03 "httpMetrics": [
04 {
05 "upstreamCacheStatus": "-",
06 "sum": 334
07 },
08 {
09 "upstreamCacheStatus": "REVALIDATED",
10 "sum": 301
11 },
12 {
13 "upstreamCacheStatus": "MISS",
14 "sum": 281
15 },
16 {
17 "upstreamCacheStatus": "HIT",
18 "sum": 50
19 },
20 {
21 "upstreamCacheStatus": "EXPIRED",
22 "sum": 16
23 }
24 ]
25 }
26}

Each row sums the requests that carry one value of upstreamCacheStatus, such as HIT, MISS, REVALIDATED, EXPIRED, or -. For every value of upstreamCacheStatus, refer to Real-Time Metrics GraphQL fields.

To find the missed content of the domain in Azion Console, with the host filter applied:

Read the missed data

On the Data Transferred dashboard, find the Missed Data entry in the legend of the Missed Data chart.

Select Requests in the dashboard selector
Read the missed requests

In the Missed Requests chart, find the Missed Requests entry in the legend.

Find the peaks

In the Missed Requests chart, place the cursor on the highest point. The tooltip shows the value at that point.

The peaks of Missed Requests show when the data center sent the most requests of the domain to your origin. The tooltip shows only in a window wider than 540 px.

Next steps

Build dashboardsWhat each chart of the Data Transferred dashboard measures, its unit, and its field.CacheChange how your applications cache content, to raise the share served from cache.Tiered CacheAdd a second cache layer between the data center and your origin.Real-Time Metrics best practicesChoose ranges, filters, and row limits that keep the numbers you read reliable.