Google's first big update for Googlebooks, its line of laptops, reworks how the system manages memory and frees up to 6GB of RAM on devices that have 16GB.
That is the one hard number attached to the release. Memory management is the operating system's job of deciding which apps and background tasks get to hold space in RAM, the short-term workspace a computer uses for everything currently open. Google changed how that allocation works, and on a 16GB machine the result can be as much as 6GB returned to the system.
The update also includes security improvements. Details on those changes were not available, so there is nothing yet to say about what they fix or whom they protect.
The arithmetic is worth a moment. Six gigabytes is 37.5% of a 16GB machine, a large slice of a configuration that is common on current laptops. The words "up to" matter, though. They describe a ceiling, and the amount a given owner recovers will depend on what is running.
Other desktop operating systems have spent years on the same problem, with techniques such as compressing idle memory pages instead of discarding them. A first major update that leads with memory suggests that is where Google sees room to improve. What an everyday workload actually gets back, with a browser full of tabs and a few apps open, is the open question.