Google Chrome is fast but it can kill your battery life when you play videos on your Windows laptop. Unlike Microsoft Edge, Google Chrome is a notorious battery hog that if left to run in the background with videos playing can reduce your laptop or tablet to just a couple of hours of life.
In 2017, a Google engineer suggested that reducing ‘vsync’ when playing full-screen videos can save power on laptops. This issue has largely been ignored but a Google engineer has recently started working on a fix again.
In a commit, Google highlighted a change that will wire up global frame rate to video and root swap chains on Windows. This may allow DWM (Desktop Windows Manager) and OS (Windows 10) to reduce vsync when video is fullscreen and iflip, which should reduce the battery usage during video playback.
In their tests, Google engineer discovered that Chrome currently keeps switching back/forth between SetFrameRate(30) and SetFrameRate(0) at least once per second and there is “roughly 24% of less CPU usage when we drop vsync to 30 fps”
“The above CL has been tested on Surface Pro 6. When we play a video of 30 fps, We successfully drop vsync,” a Google dev noted.
Microsoft engineer also jumped into the conversation when tagged and they believe that MediaFoundation integration for video will reduce wakeups to match video framerate and contribute to better performance.
“The use of custom refresh rate to match content refresh rate (it is usually much less than the 60Hz refresh rate) if driver supports it – it is part of MediaFoundation video rendering optimization for full screen video,” Microsoft dev explained.
It’s not yet clear when video playback improvements will land for Chrome, but Google engineers are now actively working on a fix.