Windows 8 news continues to trickle from the Building Windows 8 blog at a steady clip: today, Gabe Aul detailed changes to the Windows 8 boot process that promise to drastically reduce startup times.

The team wanted to come up with a startup method that would deliver the benefits of a cold boot (a "fresh session" at startup, no power usage when off) while reducing the amount of time that it takes to load the operating system from disk to RAM. 

To accomplish this, Microsoft has combined aspects of a traditional Windows shutdown with system hibernation, which saves the contents of your RAM to disk and then restores it to RAM at next boot. While a Windows shutdown currently closes all user programs (the "user session") and then all system services and processes (the "kernel session") completely before powering off, Windows 8 closes the user session and saves the rest of your RAM's content to disk. The kernel session can then be restored to RAM quickly at next boot - this is more speedy than traditional hibernation both because there's less data to restore to RAM from the disk (just the kernel session, as opposed to the kernel session and the user session), and because restoring hibernation files is a fully multithreaded process in Windows 8. If the feature works as well as it does in the Microsoft demo video, it is indeed quite impressive.

Microsoft notes that drivers are still initialized during this startup process, which means that driver and system updates should no longer require a "full" reboot of the system (something Microsoft has been promising since the Longhorn days). However, for those of you more comfortable with a traditional "full" shutdown, there are command line options to toggle the new feature on and off ("powercfg /hibernate off" which has the unfortunate side-effect of completely disabling hibernation), and also to initiate one-time full shutdowns ("shutdown /s /full").

According to Microsoft, these improvements should benefit users with SSDs and HDDs alike, and will be especially noticeable when paired with systems supporting UEFI, the BIOS replacement that is slowly being adopted by most major PC manufacturers and motherboard makers. For full details, as always, you can check out the very detailed post on the Building Windows 8 blog.

Source: Building Windows 8 Blog

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  • tipoo - Friday, September 9, 2011 - link

    You're waking your iPad up from sleep. This demonstration was from a complete power-off. Hold the power button and shut down your ipad completely, then see how long it takes to start.
  • fhaddad78 - Friday, September 9, 2011 - link

    Microsoft needs to add an MS-DOS mode for power users... o.O

    DOS and DESQview - Go!
  • Candide08 - Friday, September 9, 2011 - link

    How about going back to the BASIC ROM option on boot up? ;)
  • fhaddad78 - Friday, September 9, 2011 - link

    That would be in Windows 9
  • Candide08 - Friday, September 9, 2011 - link

    Reading a full memory and state file from disk is not fast, especially when it as a very large file. Hibernation is flaky at best and "lab results" often do not translate to the real world very well.

    In addition adding a multi-gig (8GB, 16GB) hiberfil.sys to the system drive will now mean that windows, just windows, will take up a MINIMUM of 40GB - necessitating even larger system partitions.
  • hechacker1 - Friday, September 9, 2011 - link

    if you had read the blog, you would see they aren't loading the entire memory state. They are only saving the kernel, services, registry, and driver information so that you can quickly load a "fresh" system.

    Plus they are compressing and multi-threading the read of the hiberfil.sys so it happens as fast as possible.

    You still have to log in so that it initializes the user session. That's why it's so fast to boot.
  • Candide08 - Friday, September 9, 2011 - link

    Did you learn to be such an ass, or were you born that way?

    I read the blog, I read other articles on this.
    As I said, "lab results" frequently do not apply in production.
    I still do not trust MS on this - we shall see.
  • hechacker1 - Friday, September 9, 2011 - link

    The slowest part of the boot process is reading the scattered files required for booting. Often they are tiny driver and service descriptors (4K files), hence why a SSD is much faster for booting, even without optimizing for it.

    After you have sufficient IO, the next bottleneck is loading service dependencies. The fewer the better.

    Reading a single, large and contiguous, hibernate file is much faster for the typical HDD if it contains the clean state of the system. That's why I believe Microsoft on this.

    Linux has been doing this for a while now (with varying success). They preload the files into a single preload file, and also compress and read it as fast as possible.

    I believe there are even OEM and third party utilities for Windows that do this. So basically Microsoft is just baking this into Windows 8.
  • Zak - Saturday, September 10, 2011 - link

    I have Windows 7 installed on an SSD. The longest part of my boot is the POST and the Intel Storage/RAID screens, and that's with "Quick Boot" option enabled in the BIOS. It's a P67 mobo. Are EFI boards any faster? A lowly iMac with a mechanical hard drive boots OSX faster than my super duper PC.
  • veldrane - Saturday, September 10, 2011 - link

    As is now, my PC with fresh install of windows and nothing else on it, unconnected to the web, boots up in under 15 secs flat.

    Then add the delays, login, various startup applications and connecting. That is what really makes the boot time so long, up to 2 minutes for me. Biggest Chunks of it for me, are: Firewall, anti-virus, video drivers and language packs (fonts and alternate keyboard layouts / characters included)

    I reboot my comp when and BECAUSE I need to clear memory, for example, when I know I will have to do some business online, I will scan my comp, dump all temp files, etc. then reboot to clear memory and run with extra security precautions such as different browser with different security features and settings etc., in order to better protect my private information which I have to use for business.

    If there is some malware or adware or something left over from regular everyday use, it usually gets cleared during a complete shut down and restart providing its startup is not in the registry or in the start up files, and the previous scans take care of that.

    Now, if they make it so that memory gets copied to either HD or SSD before reboot, how will I be able to clear it if it just automatically reloads at start ? The 14 seconds windows boot time is irrelevant and I really do not see what is the big deal.

    Will this feature have an on-off option ? Best case scenario I think would be if you could select specific apps to be "saved" in this manner if boot times are an issue, so that you can put your biggest time hogs in there, but once in a while you want to clear the memory, how will this be accomplished with this feature ?

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