Original URL: http://www.theregister.co.uk/2014/07/19/chrome_power_sucking_bug/

Chrome browser has been DRAINING PC batteries for YEARS

Google is only now fixing ancient, energy-sapping bug

By Neil McAllister

Posted in Applications, 19th July 2014 00:31 GMT

If you've been wondering why the battery life on your Windows laptop or tablet seems so lousy, your Chrome web browser might be to blame – and it may have been sapping your system's juice for years.

A documented bug in the source code for the Chromium open source project seems to account for the mysterious power drain that some users of Google's web browser have been experiencing.

The aggravating part for many users, however, is that the bug was first filed for Chrome version 22, way back in September 2012, yet Google has so far ignored it.

The problem has to do with how Chrome forces Windows machines to manage processor idle time. When a computer isn't doing much, it sends its CPU to sleep to save power, waking up at intervals when if there are any events that need handling. On Windows, these checks normally happen every 15.625ms, but that interval can be adjusted – and this is where Chrome goes awry.

Instead of waking up the processor every 15.625ms, Chrome tells Windows to have it wake up every 1.000ms. So while your PC normally wakes up the processor 64 times per second when it's idle, as long as you have Chrome running, the processor wakes up 1,000 times per second.

Chrome doesn't have to be running in the foreground to have this effect, either. There's only one platform timer, so when one application changes its resolution, the new value becomes a system-wide setting.

Naturally, if your system's processor is never allowed any rest, the effects of any power-management techniques will be virtually negated, and your battery will run down at a much faster rate than it should.

Unfortunately, despite repeated complaints from Chrome users over the years, as documented in Google's bug tracker database, the glitch has never been addressed – until now, that is.

Earlier this week, Forbes ran an article pointing out the lingering bug and the drain it continues to be on Windows users' machines. Shortly after it was published, the bug was assigned an official owner, just one month shy of its two-year anniversary.

"I can confirm that this bug has been assigned internally and our team is working to resolve it," a Google spokeswoman told The Reg via email on Friday.

If the bug does get addressed, it's still not clear when a patch might make its way to a mainstream, stable Chrome release. Windows users are advised to keep their eyes on Google's Chrome Releases blog for word of a fix. Linux and OS X machines, on the other hand, are believed to be unaffected by the bug. ®