We're all running systems these days with at least a couple of cores in our CPUs, right? And we want to take advantage of those cores too. Windows 8 will do that in a way that Windows 7 doesn’t – in the turning on and off of your computer.
Windows 8 will leverage multiple cores in parallel to work together when the system is preparing itself for hibernation and resume. In previous versions of Windows, this would only matter for those who were hibernating their systems; but for Windows 8, nearly all shutdown and boot sequences will use some form of hibernation.
In previous versions of Windows, every boot and shutdown sequence would be a completely fresh start for both the kernel and user sessions. The developers of Windows 8 deem the complete shutdown and reboot of the kernel session every time as unnecessary, so Windows 8 will instead hibernate the kernel session and only shutdown the user sessions.
Gabe Aul, a director of program management in Windows wrote in the B8 blog:"Now here’s the key difference for Windows 8: as in Windows 7, we close the user sessions, but instead of closing the kernel session, we hibernate it. Compared to a full hibernate, which includes a lot of memory pages in use by apps, session 0 hibernation data is much smaller, which takes substantially less time to write to disk. If you’re not familiar with hibernation, we’re effectively saving the system state and memory contents to a file on disk (hiberfil.sys) and then reading that back in on resume and restoring contents back to memory. Using this technique with boot gives us a significant advantage for boot times, since reading the hiberfile in and reinitializing drivers is much faster on most systems (30-70% faster on most systems we’ve tested)."
This means that an already fast boot process helped by an SSD gets even faster. Check out the SSD boot time in the video below: