[Update: Performance issues] Windows 10 updates may reduce Google Chrome RAM usage

Ben Schoon | Jul 14 2020 - 6:00 am PT

You’ve seen the memes. Google Chrome absolutely eats RAM on most computers, especially on Windows. Now, though, a change to Windows 10 that is live in the latest update opens the door for Google Chrome to reduce its usage going forward.

The Windows 10 May update, as the folks over at Windows Latest point out, introduces segment heap memory improvements. What is that? The short story is that it’s a method to reduce overall memory usage of Win32 apps, such as Google Chrome, on the latest versions of Windows. This change is available to developers in Windows version 2004 or newer.

“SegmentHeap” is already being used by Microsoft’s Chromium-based Edge browser as detailed in a recent blog post. When implemented, it shows a memory reduction of up to 27% in early tests.

Early internal testing results of devices on the May 2020 Update are showing a memory usage reduction of up to 27% when browsing with Microsoft Edge. Individual device performance will vary based upon configuration and usage, but the lower memory usage is expected to create a better experience.

In a Chromium commit, engineers discuss using “SegmentHeap” on Google Chrome. The engineer mentions that implementing the change could save “hundreds of MB in the browser and Network Service utility processes” on some machines, with “many-core” machines benefitting the greatest from the change.

There may be one considerable roadblock, though. Implementing “SegmentHeap” in Google Chrome for Windows would reduce RAM usage, but it would require Google to build with the Windows 10.0.19041.0 (20-04) SDK. Apparently, this is difficult because that version is “currently blocked on some mysterious build failures.” Hopefully, Google can work things out.

Be warned, though, the version 2004 update for Windows is still messing with Google Chrome for many users. If you can hold off for the time being, do so.

Update 7/14: Google had SegmentHeap ready to go for Chrome 85, but the release has been disabled and delayed. Why? Performance issues.

As TechDows notes, Chrome engineers have found that implementing this feature can help save on RAM use, but it comes at the cost of increased CPU usage. Currently, engineers are concerned that using this feature “doesn’t justify its cost.” Yikes.

For now, SegmentHeap implementation on Google Chrome isn’t arriving with v85, but rather will arrive with a later release. An engineer explains:

Although I have heard encouraging things about memory savings from lab tests I don’t see any way for us to leave this enabled until we have clean telemetry data and lab tests on 20H1, neither of which will be happening in time for M85.

So, the plan is to disable this for M85 (thus giving us another telemetry datapoint) and reconsider in the future.

The CPU cost (10% slowdown on Speedometer 2.0, 13% increase in CPU/power consumption) is too great for us to keep.