Those of you who saw Microsoft demonstrate Windows 8 at their Build conference last month will know that Windows 8 uses less RAM than Windows 7. Microsoft used a low powered netbook which had just 1GB of RAM. They booted Windows 7 SP1 and the Windows 8 Developer Preview and after they had both been at idle for a while it was found that Windows 8 was using a lot less CPU and Memory compared to Windows 7. ( 5% vs 1% and 404 MB vs 281 MB)
Windows 7 was applauded for reducing the amount of memory that Windows uses, especially compared to Windows Vista but now Microsoft have gone even further with Windows 8. One of their goals was to make sure that all machines that are capable of running Windows 7, will be able to run Windows 8 without a problem. Microsoft have managed to surpass these expectations by making Windows 8 even less resource intensive.
So how do they do it? Well Microsoft went into great detail over on the Building Windows 8 blog but I’ll try and just give you some of the main points.
Windows 8 make use of a new feature known as memory combining. Basically Windows looks at system RAM use, then it finds duplicate code that could be running for a variety of reasons, it then removes these duplicates from the memory so that you only have one copy of the code running, thus freeing up memory.
The number of background process that Windows 8 uses has also been reduced by 13. This is quite a large amount and should make a big difference and increase performance.
Even the new Metro interface helps reduce memory usage, although it’s only really for tablets. When you’re using a tablet, Windows 8 won’t actually load up the desktop components for the OS because the chances are you’re not going to bother using the traditional desktop if you’re using a tablet. Of course if you do decide to switch to your desktop it will still load them up, but not running these components saves around 23MB or RAM in the developer preview edition of Windows 8.
There’s a whole host of little tricks that Microsoft are using to reduce memory usage in Windows 8 and while I’ve only touched on them, you can read into them in more detail here on their blog