https://github.com/aslushnikov/tracium

A blessed Chrome Trace parser.
https://github.com/aslushnikov/tracium

Last synced: 6 days ago
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A blessed Chrome Trace parser.

• Host: GitHub
• URL: https://github.com/aslushnikov/tracium
• Owner: aslushnikov
• License: apache-2.0
• Created: 2019-04-25T06:45:53.000Z (over 5 years ago)
• Default Branch: master
• Last Pushed: 2019-06-18T16:56:53.000Z (over 5 years ago)
• Last Synced: 2024-10-17T15:58:17.821Z (27 days ago)
• Language: JavaScript
• Homepage:
• Size: 490 KB
• Stars: 72
• Watchers: 8
• Forks: 7
• Open Issues: 9
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# Tracium

*Tracium* is the [Google Lighthouse](https://github.com/GoogleChrome/lighthouse)

tracing parser extracted into a stand-alone library.

Tracium is a modern alternative to [Big Rig](https://github.com/googlearchive/node-big-rig).

Tracium correctly parses modern Chrome Traces (generated by Chrome 66+).

## Usage

Install:

```

$ npm install tracium

```

Use:

```js

const Tracium = require('tracium');

const traceJSON = JSON.parse(fs.readFileSync('./mytrace.json', 'utf8'));

const tasks = Tracium.computeMainThreadTasks(traceJSON, {

  // |flatten| default to |false|. When false, only top-level tasks will be returned.

  flatten: true,

});

```

Check out examples at [//examples/](https://github.com/aslushnikov/tracium/tree/master/examples) folder.

## API

#### tracium.computeMainThreadTasks(traceJson[, options])

- `traceJson` <[Object]> A JSON of a Chromium trace

- `options` <[Object]>  Set of options for trace processing

  - `flatten` <[boolean]> Defaults to `false`. Whether to flatten tasks tree. 

- returns: <[Array]<[Object]>> An array of tasks:

  - `kind` <[string]> describes task attribution. Can be one of the following:

    - `'parseHTML'`

    - `'styleLayout'`

    - `'paintCompositeRender'`

    - `'scriptParseCompile'`

    - `'scriptEvaluation'`

    - `'garbageCollection'`

    - `'other'`

  - `startTime` <[number]> monotonic start time in milliseconds

  - `endTime` <[number]> monotonic end time in milliseconds

  - `duration` <[number]> task duration in milliseconds, a.k.a. "wall time"

  - `selfTime` <[number]> time spent in the task at the current level of the task tree

  - `event` <[Object]> original trace event object associated with the task

  - `children` <[Array]<[Task]>> an array of child tasks

  - `parent` [Task]> a parent task if any

Returns an array of tasks that belong to the main thread of the inspected page.

If `flatten` is passed to `false`, than only top-level tasks will be returned.

An example task

```

{

  event:

   { pid: 29772,

     tid: 775,

     ts: 588826692280,

     ph: 'X',

     cat: 'toplevel',

     name: 'TaskQueueManager::ProcessTaskFromWorkQueue',

     args:

      { src_file: '../../base/trace_event/trace_log.cc',

        src_func: 'SetEnabled' },

     dur: 27,

     tdur: 22,

     tts: 514358 },

  startTime: 0,

  endTime: 0.027,

  children: [],

  duration: 0.027,

  selfTime: 0.027,

  kind: 'other' }

```

[Array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array "Array"

[boolean]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type "Boolean"

[Buffer]: https://nodejs.org/api/buffer.html#buffer_class_buffer "Buffer"

[function]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function "Function"

[number]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type "Number"

[Object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object "Object"

[origin]: https://developer.mozilla.org/en-US/docs/Glossary/Origin "Origin"

[Promise]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise "Promise"

[string]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type "String"

[stream.Readable]: https://nodejs.org/api/stream.html#stream_class_stream_readable "stream.Readable"

[Error]: https://nodejs.org/api/errors.html#errors_class_error "Error"

[ChildProcess]: https://nodejs.org/api/child_process.html "ChildProcess"

[iterator]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols "Iterator"

[Element]: https://developer.mozilla.org/en-US/docs/Web/API/element "Element"

[Map]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map "Map"

[selector]: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors "selector"

[Serializable]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#Description "Serializable"

[xpath]: https://developer.mozilla.org/en-US/docs/Web/XPath "xpath"

[UnixTime]: https://en.wikipedia.org/wiki/Unix_time "Unix Time"