Chrome 57 Conserves Battery Life And Boosts Performance By Throttling Greedy Background Tabs

Google Chrome is the most dominant desktop web browser on the market, but it isn’t without its critics. While the browser is extremely versatile and generally provides excellent overall performance, those pluses often comes at the expense of higher memory usage and a penchant for chewing through CPU cycles (and memory), which in turn reduces battery life on mobile devices.

Google is taking steps to vanquish is power hog demons with the release of Chrome 57. The latest iteration of Chrome was actually released last week, but Google only recently gave us details on what exactly changed with this latest build. Chrome 57 now throttles individual background tabs to ensure that they don’t continue to use CPU cycles while you’re focusing on other tasks. According to Google’s Alexander Timin, the Chrome team has specifically limited the “timer fire rate” on these offending tabs.

So, how far will Chrome 57 throttle background tabs? According to Timin, timers will be throttled down to an average CPU load of 1 percent if a tab attempts to hog CPU resources in the background. This new change in background tab behavior, however, is ignored if a tab is playing audio or handling real-time chat sessions.

What this means in terms of your everyday usage is that you’ll will find that Chrome 57 will spend less time dragging down your CPU and should help to improve the battery life of your notebook or convertible when you’re away from the power outlet. The changes also mean that Chrome 57 will on average have 25 percent fewer busy tabs duking it out in the background. 

“Chrome will continue to take steps in this direction to prolong users' battery life, while still enabling all the same experiences developers can build today,” Timin continues.

This is just a small step, however, in Google efforts to make Chrome’s power efficiency match its might in browser market share. Looking forward, Google is aiming to take additional measures [Google Doc] including suspending all tasks on mobile and throttling non-timer tasks (both of these functions will be implemented during Q2).

Looking further out, Google is looking into “Budget-based throttling for off-screen frames”, throttling web workers, suspending all background tabs, and eventually removing opt-outs. However, that last function won’t be enabled until sometime in the next decade.