FYI to all you people using tiny drives in 2019, your available disk space will drop by 7GB, so if you check your boot disk's properties, ensure you have at least 7GB remaining before you install what will become Windows 10 1903.
How does it work?
When apps and system processes create temporary files, these files will automatically be placed into reserved storage. These temporary files won’t consume free user space when they are created and will be less likely to do so as temporary files increase in number, provided that the reserve isn’t full. Since disk space has been set aside for this purpose, your device will function more reliably. Storage sense will automatically remove unneeded temporary files, but if for some reason your reserve area fills up Windows will continue to operate as expected while temporarily consuming some disk space outside of the reserve if it is temporarily full.
Windows Updates made easy
Updates help keep your device and data safe and secure, along with introducing new features to help you work and play the way you want. Every update temporarily requires some free disk space to download and install. On devices with reserved storage, update will use the reserved space first.
When it’s time for an update, the temporary unneeded OS files in the reserved storage will be deleted and update will use the full reserve area. This will enable most PCs to download and install an update without having to free up any of your disk space, even when you have minimal free disk space. If for some reason Windows update needs more space than is reserved, it will automatically use other available free space. If that’s not enough, Windows will guide you through steps to temporarily extend your hard disk with external storage, such as with a USB stick, or how to free up disk space.
How much of my storage is reserved?
In the next major release of Windows (19H1), we anticipate that reserved storage will start at about 7GB, however the amount of reserved space will vary over time based on how you use your device. For example, temporary files that consume general free space today on your device may consume space from reserved storage in the future. Additionally, over the last several releases we’ve reduced the size of Windows for most customers. We may adjust the size of reserved storage in the future based on diagnostic data or feedback. The reserved storage cannot be removed from the OS, but you can reduce the amount of space reserved. More details below.
The following two factors influence how reserved storage changes size on your device:
- Optional features. Many optional features are available for Windows. These may be pre-installed, acquired on demand by the system, or installed manually by you. When an optional feature is installed, Windows will increase the amount of reserved storage to ensure there is space to maintain this feature on your device when updates are installed. You can see which features are installed on your device by going to Settings > Apps > Apps & features > Manage optional features. You can reduce the amount of space required for reserved storage on your device by uninstalling optional features you are not using.
- Installed Languages. Windows is localized into many languages. Although most of our customers only use one language at a time, some customers switch between two or more languages. When additional languages are installed, Windows will increase the amount of reserved storage to ensure there is space to maintain these languages when updates are installed. You can see which languages are installed on your device by going to Settings > Time & Language > Language. You can reduce the amount of space required for reserved storage on your device by uninstalling languages you aren’t using.