Huge memory usage

[KindOf]

We are reading big xlsx file (~60k cells and 6mb). process.memoryUsage shows:

{
  rss: 506667008,
  heapTotal: 247668736,
  heapUsed: 213031496,
  external: 210783589
}

After that we need to parse it as a json using XLSX.utils.sheet_to_json().
process.memoryUsage() now shows:

{
  rss: 1075920896,
  heapTotal: 909008896,
  heapUsed: 865942592,
  external: 120989339
}

Idle process - something like 100 mb memory.
Is there any way to parse it partially?

[SheetJSDev]

@KindOf You aren't the only one to notice the problem! After looking into #764 it seems to be a nodejs issue: nodejs/node#14652

Can you try reverting back to node 4.x? See the triage of the issue

[reviewher]

Reported to V8: https://bugs.chromium.org/p/v8/issues/detail?id=6696