| <!DOCTYPE html> |
| <html> |
| <body> |
| <script src="../../resources/runner.js"></script> |
| <script> |
| "use strict"; |
| |
| const targetBounces = 1000; |
| |
| let currentSender = null; |
| let currentReceiver = null; |
| let bouncesRemaining = 0; |
| let iterationStart = 0; |
| |
| function onReceive() |
| { |
| if (--bouncesRemaining === 0) { |
| const elapsed = PerfTestRunner.now() - iterationStart; |
| if (!PerfTestRunner.measureValueAsync(elapsed)) |
| return; |
| setTimeout(runIteration, 0); |
| return; |
| } |
| bounce(); |
| } |
| |
| function bounce() |
| { |
| const channel = new MessageChannel(); |
| currentSender = channel.port1; |
| currentReceiver = channel.port2; |
| currentReceiver.onmessage = onReceive; |
| currentSender.postMessage(0); |
| } |
| |
| function runIteration() |
| { |
| bouncesRemaining = targetBounces; |
| iterationStart = PerfTestRunner.now(); |
| bounce(); |
| } |
| |
| PerfTestRunner.prepareToMeasureValuesAsync({ |
| description: 'Time to deliver ' + targetBounces + ' messages, each on a freshly ' |
| + 'constructed same-context MessageChannel. Measures combined channel-construction ' |
| + 'plus single-message-delivery cost. This kind of logic is representative of a ' |
| + 'requestIdleCallback() polyfill found on the web', |
| unit: 'ms', |
| }); |
| |
| setTimeout(runIteration, 0); |
| </script> |
| </body> |
| </html> |
