Programmatically get memory usage in Chrome

Question

How can I programmatically get memory usage (JS and total) of my website in Google Chrome?

I looked at doing it from a Chrome extension using the undocumented HeapProfiler (see here), but I can't find a way to get data from that.

I want to measure the memory consumption it at every release, so this needs to be programmatic.

EDIT: I figured out how to get the HeapProfiler method to work. Each addHeapSnapshotChunk event has a chunk of a JSON object.

chrome.browserAction.onClicked.addListener(function(tab) {
  var heapData,
    debugId = {tabId:tab.id};
  chrome.debugger.attach(debugId, '1.0', function() {    
    chrome.debugger.sendCommand(debugId, 'Debugger.enable', {}, function() {
      function headerListener(source, name, data) {
        if(source.tabId == tab.id && name == 'HeapProfiler.addProfileHeader') {
          function chunkListener(source, name, data) {
            if(name == 'HeapProfiler.addHeapSnapshotChunk') {
              heapData += data.chunk;
            } else if(name == 'HeapProfiler.finishHeapSnapshot') {
              chrome.debugger.onEvent.removeListener(chunkListener);
              chrome.debugger.detach(debugId);
              //do something with data
              console.log('Collected ' + heapData.length + ' bytes of JSON data');
            }
          }
          chrome.debugger.onEvent.addListener(chunkListener);
          chrome.debugger.sendCommand(debugId, 'HeapProfiler.getHeapSnapshot', {uid:data.header.uid, type:data.header.typeId});
        }
        chrome.debugger.onEvent.removeListener(headerListener);
      }
      chrome.debugger.onEvent.addListener(headerListener);
      chrome.debugger.sendCommand(debugId, 'HeapProfiler.takeHeapSnapshot');
    });
  });
});

When parsed, the JSON has nodes, edges, and descriptive metadata about the node and edge types and fields.

Alternatively, I could use Timeline events if I just want totals.

That said, are there any better ways than what I've found out here?

Answer 1

Just an update on this thread: Starting chrome 83, performance.measureMemory() seems to be most reliable way to get memory information on chrome. It gives us the exact memory information even if the same heap is shared by multiple web pages!!. You can find more info at: https://web.dev/monitor-total-page-memory-usage/

Answer 2

The chrome dev channel has a process api, chrome.process. You can query it for a tab's process information, which includes all kinds of memory information. http://developer.chrome.com/extensions/processes.html

Answer 3

For anyone that finds this in the future, since version 20 Chrome supports window.performance.memory, which returns something like:

{
  totalJSHeapSize: 21700000,
  usedJSHeapSize: 13400000,
  jsHeapSizeLimit: 1620000000
}

Answer 4

There is a js library for that: https://github.com/spite/memory-stats.js

Answer 5

An alternative approach: write a web page scraper pointing to this URL:

chrome://system/

(note: in case this URL changes again, this is the 'master' URL that lists all the chrome diagnostic pages: chrome://chrome-urls/

the page has a section 'mem_usage' that gives details of memory usage.

maybe there is some way to script Chrome as a user (say in AutoIT or Python?) that loads this URL in Chrome, and then presses the Update button, and then parses the JSON to get the memory usage for whatever tabs you are interested in.

---

OTHER approaches:

• from JavaScript - use window.performance

• from JavaScript - use browser-report.js -

https://www.npmjs.com/package/browser-report