What Windows XP Brings to Storage

The upcoming version of the Windows OS, formerly known as Whistler but now branded Windows XP, contains several new storage-related features that many users will find valuable. Because I haven't yet tested beta versions of XP, I can't say how well these new features work. I can, however, review how the features can impact your work, and in future columns I'll describe my experiences testing the following six new XP storage features:

Microsoft is building storage APIs that vendors can use in their products, and snapshot technology is one example. One part of the API is a COM infrastructure that performs registration and configuration. The COM coordinator service provides driver messages between applications and snapshot process services, and it uses a copy-on-write design to perform discovery. XP also provides interfaces to support Independent Software Vendor (ISV)/Independent Hardware Vendor (IHV) plugins of other snapshots.

Organizations increasingly use snapshots as storage volume sizes rise and backup windows decrease. A snapshot of a storage volume is a point-in-time copy. Most people use snapshots as one kind of backup because they provide a versioning of volume changes, but the technology can also provide asynchronous replication.

A related new XP feature is backup snapshot integration. Users can set snapshots to capture an image of all files. If an application or service doesn't implement a snapshot writer, XP will back up the data. The API notifies snapshot-aware services at restore time to let a user recover data during a restore operation using the metadata contained in the snapshot.

Microsoft is also adding ASR to the file system improvements. ASR saves and restores applications using a Plug and Play (PnP) mechanism stored in the registry. When a server's hard disk fails, losing its configuration parameters and information, the server can use ASR to restore files from the backup of the server's original data.

Most users will appreciate Microsoft's inclusion of a CD-burning utility. Although this new XP feature is unlikely to replace available third-party CD-burning applications, the XP software will help make this technology even more popular.

Because most of us transfer files over the Internet and attach them to emails, it's hard to avoid using zip files on Windows. Many OSs (e.g., Sun Solaris) offer compression and decompression support directly from the GUI. In XP, Microsoft lets users create zip files and view the contents of zipped folders. Microsoft's zip feature probably won't replace software such as WinZip, but many users will appreciate having a bundled compressed-folder utility.

The final new XP storage feature is the enhanced version of Disk Defragmenter that comes with a new GUI, command-line support, and new file-system APIs. You can use the GUI to launch or suppress snapshots. The command line lets administrators script a defragmentation task on a volume-by-volume basis. In addition, a new file-system API supports the defragmenter to assure that the user's system cache doesn't try to defragment data.

The new storage APIs will improve many vendors' products, and anything that gets the general public to adopt snapshot technology is a good thing. I'm convinced that more people will back up their data with snapshots than with full or incremental snapshot technology. The rest of the XP storage-related changes seem evolutionary, but they make sense.