react-addons-perf doesn't measure anything

[1st8]

Description

When using react-addons-perf, the result of Perf.getLastMeasurements() always returns an empty array, although there were updates happening between the calls to Perf.start() and Perf.stop().

Reproduction

Create a fresh react-native project and apply the following changes: 1st8/PerfNative2@9916526
Now open the app and start debugging in chrome. In the console, select the "debuggerWorker.js" environment to get access to the global Perf object.
Then run Perf.start(), click the plus-button a few times and finalize with running Perf.stop().
The following call to Perf.getLastMeasurements() is expected to return measurements of your actions, but returns none.
I did a similar test with a fresh create-react-app project and got the expected result.

Solution

Sadly no idea...

Additional Information

• React Native version: 0.40.0
• Platform: both
• Operating System: MacOS

[24ark]

@1st8 You can use RCTRenderingPerf.js instead of react-addons-perf.

import PrefMonitor from 'react-native/Libraries/Performance/RCTRenderingPerf';

componentDidMount() {

  PrefMonitor.toggle();
  PrefMonitor.start();
  setTimeout(() => {
      PrefMonitor.stop();
  },5000);

}

[lslima91]

@24ark this gives me "Failed to execute 'measure' on 'WorkerPerformance': The mark '163::ctor' does not exist"

[seanadkinson]

Using react-native@0.39 was able to get access to a working Perf using:

var Perf = require('ReactPerf');

After measuring, it seems to be displaying useful information in the console using Perf.printInclusive().

[teameh]

@24ark PrefMonitor works fine for me (0.44), thanks! I've made a small PR to at least have something that works in the docs. #13902

[hramos]

Hi there! This issue is being closed because it has been inactive for a while. Maybe the issue has been fixed in a recent release, or perhaps it is not affecting a lot of people. Either way, we're automatically closing issues after a period of inactivity. Please do not take it personally!

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