Note: This feature is available in Web Workers.
Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The PerformanceServerTiming
interface surfaces server metrics that are sent with the response in the Server-Timing
HTTP header.
This interface is restricted to the same origin, but you can use the Timing-Allow-Origin
header to specify the domains that are allowed to access the server metrics. Note that this interface is only available in secure contexts (HTTPS) in some browsers.
Properties
PerformanceServerTiming.description
Read only- A
DOMString
value of the server-specified metric description, or an empty string. PerformanceServerTiming.duration
Read only- A double that contains the server-specified metric duration, or value
0.0
. PerformanceServerTiming.name
Read only- A
DOMString
value of the server-specified metric name.
Methods
PerformanceServerTiming.toJSON()
- Returns a
DOMString
that is the JSON representation of thePerformanceServerTiming
object.
Example
Given a server that sends the Server-Timing
header, for example a node.js server like this:
const http = require('http'); function requestHandler(request, response) { const headers = { 'Server-Timing': ` cache;desc="Cache Read";dur=23.2, db;dur=53, app;dur=47.2 `.replace(/\n/g, '') }; response.writeHead(200, headers); response.write(''); return setTimeout(_ => { response.end(); }, 1000) }; http.createServer(requestHandler).listen(3000).on('error', console.error);
The PerformanceServerTiming
entries are now observable from JavaScript via the PerformanceResourceTiming.serverTiming
property:
let entries = performance.getEntriesByType('resource'); console.log(entries[0].serverTiming); // 0: PerformanceServerTiming {name: "cache", duration: 23.2, description: "Cache Read"} // 1: PerformanceServerTiming {name: "db", duration: 53, description: ""} // 2: PerformanceServerTiming {name: "app", duration: 47.2, description: ""}
Specifications
Specification | Status | Comment |
---|---|---|
Server Timing The definition of 'PerformanceServerTiming' in that specification. |
Working Draft | Initial definition. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PerformanceServerTiming | Chrome Full support 65 | Edge Full support ≤79 | Firefox Full support 61 | IE No support No | Opera Full support 52 | Safari ? | WebView Android Full support 65 | Chrome Android Full support 65 | Firefox Android Full support 61 | Opera Android Full support 47 | Safari iOS ? | Samsung Internet Android Full support 9.0 |
description | Chrome Full support 65 | Edge Full support ≤79 | Firefox Full support 61 | IE No support No | Opera Full support 52 | Safari ? | WebView Android Full support 65 | Chrome Android Full support 65 | Firefox Android Full support 61 | Opera Android Full support 47 | Safari iOS ? | Samsung Internet Android Full support 9.0 |
duration | Chrome Full support 65 | Edge Full support ≤79 | Firefox Full support 61 | IE No support No | Opera Full support 52 | Safari ? | WebView Android Full support 65 | Chrome Android Full support 65 | Firefox Android Full support 61 | Opera Android Full support 47 | Safari iOS ? | Samsung Internet Android Full support 9.0 |
name | Chrome Full support 65 | Edge Full support ≤79 | Firefox Full support 61 | IE No support No | Opera Full support 52 | Safari ? | WebView Android Full support 65 | Chrome Android Full support 65 | Firefox Android Full support 61 | Opera Android Full support 47 | Safari iOS ? | Samsung Internet Android Full support 9.0 |
toJSON | Chrome Full support 65 | Edge Full support ≤79 | Firefox Full support 61 | IE No support No | Opera Full support 52 | Safari ? | WebView Android Full support 65 | Chrome Android Full support 65 | Firefox Android Full support 61 | Opera Android Full support 47 | Safari iOS ? | Samsung Internet Android Full support 9.0 |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.