Check Node stream memory usage

streamMem.js

// https://nodejs.org/api/process.html#process_process_memoryusage

let rssMax = heapTotalMax = heapUsedMax = externalMax = 0;
let rssMin = heapTotalMin = heapUsedMin = externalMin = Number.MAX_SAFE_INTEGER;

readable.on('data', () => {
  const x = process.memoryUsage();
  if (x.rss > rssMax) rssMax = x.rss;
  if (x.heapTotal > heapTotalMax) heapTotalMax = x.heapTotal;
  if (x.heapUsed > heapUsedMax) heapUsedMax = x.heapUsed;
  if (x.external > externalMax) externalMax = x.external;
  
  if (x.rss < rssMin) rssMin = x.rss;
  if (x.heapTotal < heapTotalMin) heapTotalMin = x.heapTotal;
  if (x.heapUsed < heapUsedMin) heapUsedMin = x.heapUsed;
  if (x.external < externalMin) externalMin = x.external;
});

readable.on('end', () => {
  console.log({rssMin, heapTotalMin, heapUsedMin, externalMin});
  console.log({rssMax, heapTotalMax, heapUsedMax, externalMax});
});