Chrome has focused on improving the user experience by throttling tab performance for many years. Like many browsers, Chrome has limited timers in the background to only run once per second. Via the new throttling policy, Chrome 57 will delay timers to limit average CPU load to 1% of a core if an application uses too much CPU in background. Tabs playing audio or maintaining real-time connections like WebSockets or WebRTC won’t be affected.According to Google, the new throttling mechanism leads to fewer busy background tabs, which typically consume a third of Chrome's power usage on desktop computers. In the long term, Google aims to fully suspend timers in background tabs and instead rely on new APIs to do the work instead.
Chrome 57 is available to download for Mac users now. Existing users can update by selecting Chrome -> Preferences via the menu bar and clicking the About section. Users downloading Chrome for the first time will automatically receive the updated version from the Chrome download page. An update for the iOS browser app has also been released with a new Read Later option.