Requires node. Written using node 11.13.
> npm install
> node parser.js input.json [options]
Options are -a and -k.
-a : Aggregate mode.
-k : Keys mode.
This tool takes an input JSON, generates an out.json file with the performance data, then starts a local express node app to visualize the data using D3 using d3-flame-graph. The performance information is a breakdown of the raw size of the JSON object and subobjects. A few simple examples are in the test.js file. The images below were made from generated.json.
Without any optional parameters, you will see every composite object. Unfortunately, that output often is impossible to read:
It’s a long array of the same object. Long lists of items are common and thus I added an extra mode: “(-a)ggregate mode”.
Aggregate mode goes through an array and acts as if each of its child objects are the same object, summing up their contributions into a single object.
This lets you take the first graph, and coalesce it into something much easier to parse visually:
I also added another optional mode: “(-k)eys mode”. The difference there is only that the objects keys are included in its representation. This makes a big difference if you are looking to determine excessively long keys and their contributions to the greater object. Generally, I find it provides a clearer representation to what is going on in the object, so I recommend using it as well.