Released last week to Mac, Windows, and Linux, one significant improvement in Chrome 57 reduces the power consumption of tabs in the background. This stricter throttling policy should result in 25% fewer busy background tabs, according to Google.
On desktops, background tabs consume a third of Chrome’s power usage. The browser has long throttled tab performance in order to prolong battery life and improve the general user experience. Specifically, Chrome limited background timers — code that executes at set intervals — to only run once per second.
In version 57, the browser will delay timers to limit average CPU load to 1% of a core if an application uses too much CPU in the background. Intensive services that play audio or maintain real-time connections, like chatting through WebRTC, will be excluded.
With power efficiency being a core principle behind Chrome, the end goal is to fully suspended background tabs, with new API service workers to maintain work in the background.
For desktops, Chrome 57 is a more subdued update that adds support for CSS Grid Layout to aid in responsive design development and patches up other security issues. Last release, Chrome improved the bandwidth and power efficiency of page reloads, while optimizations to Chrome’s rendering pipeline also improved power draw, speed, and general smoothness.