Windows 8 will tame data loss and storage bloat on PCs by offering a simple form of the thin provisioning and virtualisation technology more commonly found in data centres, Microsoft has said.
In common with its OS rivals, current versions of Windows manage storage in a way that has barely changed in a quarter of a century and the era of DOS.
Each drive is assigned a drive letter, with the user left to remember which data is stored on which drive or partition, and how and where these have been synchronised or backed up. When data is backed up it is often archived on external USB drives, which despite rarely being filled anywhere near their capacity have a habit of multiplying in ways that make them complex to manage.
Microsoft hopes it can sweep all of this away with a new virtualisation layer called Storage Spaces.
Windows 8 users will be able to create or format a pool of drives (internal SATA drives or, more likely, external USB, Serial attached SCSI or eSata drives), which can then be organised into one or more ‘spaces’ which appear as single, logical physical drives under any chosen drive letter.
Depending on the number of drives available, users will be able to choose different levels of redundancy, with either two-way mirroring (for two-drive pools), three-way mirroring (three-drive pools) and parity (a kind of basic RAID approach but more space-efficient for large data files such as video).
For consumers, the first convenience will be the ability to reconstruct data in the event that one or more drive fails using parity data held on the others.
A second more subtle feature will be ‘thin provisioning’, that is the ability to create spaces that are much larger than the actual physical capacity of the drives making up the storage pool.
This offers huge efficiency. Today, drives are often discarded or rendered obsolete long before they are filled; thin provisioning simply tells the user to add another drive to the pool as the physical capacity becomes used up. The user never actually needs to think about how much space they have or whether an individual drive has enough capacity for a particular storage need.
Getting close to the features offered by Storage Pools would hitherto have require the expense of hardware RAID and some additional software or a multi-drive NAS drive. Microsoft also previously offered the similar Drive Extender in Windows Home Server, before that was dropped in 2010.
Reading between the lines of a long blog on Storage Spaces by Microsoft’s Steven Sinofsky, the technology will have some limitations. It’s not clear, for instance, how well it will scale. The technology has been tested up to hundreds of drives per pool, but few PCs will be able to accommodate more than a handful given the availability of USB ports and possible I/O issues.
On the upside, pools of drives will be portable, that is it will be possible to migrate them from one Windows 8 PC to another without having to start from scratch.
Storage Pools could end up being a premium feature that customers will get if they buy or upgrade to the Ultimate version of the OS although this has not been confirmed by Microsoft.