I have to test memory usage of some pages in Chrome on Windows programmatically.

Here is my Chrome version (60.0.3112.113 - Official Build - 64-bit)

Following Chromium Command Line Switches Documentation I ran Chrome with --enable-precise-memory-info flag:

Then in the opened Chrome instance I tried to check value of window.performance.memory.usedJSHeapSize

but looks like inspite of --enable-precise-memory-info flag this info is still bucketized.

even in Chrome Task Manager (Shift + Esc) I see that memory usage is grows up by about 1 Mb after each execution of:

for(let i=0;i<100000;i++) {a.push('sdftgkljhghertyukytedtreut56ytirty7uikty' +i)}

I found only one outdated discussion concerning this issue even if the issue exists I would expect to find more discussions online.

If I do something wrong - what is my mistake?

If this flag is not supported anymore then what is the new correct way to do it?

Thank you!

I have to test memory usage of some pages in Chrome on Windows programmatically.

Here is my Chrome version (60.0.3112.113 - Official Build - 64-bit)

Following Chromium Command Line Switches Documentation I ran Chrome with --enable-precise-memory-info flag:

Then in the opened Chrome instance I tried to check value of window.performance.memory.usedJSHeapSize

but looks like inspite of --enable-precise-memory-info flag this info is still bucketized.

even in Chrome Task Manager (Shift + Esc) I see that memory usage is grows up by about 1 Mb after each execution of:

for(let i=0;i<100000;i++) {a.push('sdftgkljhghertyukytedtreut56ytirty7uikty' +i)}

I found only one outdated discussion concerning this issue even if the issue exists I would expect to find more discussions online.

If I do something wrong - what is my mistake?

If this flag is not supported anymore then what is the new correct way to do it?

Thank you!

• javascript
• google-chrome
• google-chrome-devtools
• chromium

• Er, actually it sounds like a bug worth reporting on crbug. – woxxom Commented Sep 17, 2017 at 14:26
• @wOxxOm Good idea. I've opened a new issue there: bugs.chromium/p/chromium/issues/detail?id=765998 – Alexander Commented Sep 17, 2017 at 17:03
• @Alexander Was an instance of Chrome open when you launched second instance of Chrome with flag set? – guest271314 Commented Sep 18, 2017 at 2:07
• @guest271314 Thank you. Yes, I closed all the instances and even checked in Task Manager that there is no any Chrome process running. But I still see the same behavior. – Alexander Commented Sep 18, 2017 at 9:05
• 1 @Alexander Cannot reproduce at Chromium 60. Have you tried launching with --user-data-dir set to a different directory than default Chrome configuration folder? – guest271314 Commented Sep 18, 2017 at 9:05

3 Answers 3

I didn't find the reason why --enable-precise-memory-info doesn't work, so any help with that will be appritiated.

Meanwhile I found another way to do it even and I decided to share it.

I created a chrome extension and added a listener for chrome.processes.onUpdatedWithMemory in its background.js.

It gives me updated information concerning chrome processes including memory usage (the privateMemory field), but this solution has two problems:

1. To use chrome.processes I have to run the extension on Dev channel only.
2. Collecting memory usage information this way incurs extra CPU usage.

In Chrome 68+ you can now sample once every 50ms for scripts served from the same origin as the webpage (eTLD+1). This means you probably don't need --enable-precise-memory-info anymore.

https://chromium.googlesource./chromium/src/+/7c7847f69de403f6c798dfccba10812039a60480

maybe you need to close all opened chrome window (cmd + q) before run /Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --enable-precise-memory-info