Chrome Experiment: Process sharing

Dave Tapuska
Dave Tapuska

If you see a message stating "This tab shares resources with other tabs..." infobar while DevTools is open, then you are part of the small group with the Process sharing experiment enabled. This post explains the experiment.

The "This tab shares resources with other tabs, which could interfere with debugging." infobar.

What's the experiment about?

Normally, when you open multiple tabs from the same website (like Google Docs), Chrome creates a separate renderer process for each. The Process sharing experiment changes this by allowing multiple tabs to share the same renderer process.

The goal is to improve performance. For example, faster page loads, improved (LCP), and lower memory use. You can learn more in this detailed document.

How does this affect developer experience in Chrome DevTools?

Since tabs might share a process (and its main thread), there are two impacts on debugging and performance analysis:

Breakpoint debugging. If you pause the debugger in one tab, it can affect others sharing the process. You'll see the "Debugger paused in another tab, click to switch to that tab." warning. Performance analysis. Heap snapshots and performance recordings might capture data from multiple tabs, making results harder to interpret.

The "Debugger paused in another tab, click to switch to that tab." warning.

Opting in or out of the experiment

Who's opted out by default

This experiment is turned off by default for the following users:

Opting out

You can manually opt out by clicking the Opt Out button in the warning. Or, disable the Enable ProcessPerSite up to main frame threshold experiment using Chrome flags settings (chrome://flags/#enable-process-per-site-up-to-main-frame-threshold).

The Opt out button in the Process sharing infobar.

Opting In

To explicitly test the new experiment feature, launch Chrome with the following command line flags:

--enable-features=ProcessPerSiteUpToMainFrameThreshold:ProcessPerSiteMainFrameThreshold/20 -disable-features=ProcessPerSiteSkipDevtoolsUsers,ProcessPerSiteSkipEnterpriseUsers

Feedback

We'd love to hear your feedback on the Process sharing experiment! Share your questions or any issues you encounter in this feedback tracker.

Download the preview channels

Consider using the Chrome Canary, Dev or Beta as your default development browser. These preview channels give you access to the latest DevTools features, test cutting-edge web platform APIs, and find issues on your site before your users do!

Getting in touch with the Chrome DevTools team

Use the following options to discuss the new features and changes in the post, or anything else related to DevTools.

  • Submit a suggestion or feedback to us via crbug.com.
  • Report a DevTools issue using the More options   More   > Help > Report a DevTools issues in DevTools.
  • Tweet at @ChromeDevTools.
  • Leave comments on our What's new in DevTools YouTube videos or DevTools Tips YouTube videos.