released a new blog post on their Windows 8 development blog. The post, written by Bryan Matthew, a program manager on the Storage & File System team discusses the work they have done focused on scale and capacity. They identify two key challenges regarding data management on really large drives:
- Ensuring that the entire available capacity is addressable, so as to enable full utilization
- Supporting the hard disk drive vendors in their effort to deliver more efficiently managed physical disks – 4K (large) sector sizes
…the UEFI specification was developed as a replacement for BIOS and implementations have existed since the late 1990s. UEFI was designed from the ground up to work with very large capacity drives by utilizing the GUID partition table, or GPT…Beginning with Windows 8, multiple new capabilities within Windows will necessitate UEFI. The combination of UEFI firmware + GPT partitioning + LBA allows Windows to fully address very large capacity disks with ease.Microsoft are saying that they fully expect Windows 8 to install on disks larger than 3 Terabytes. In addition, they are stating that Windows 8 is the first OS with full support for both types of AF disks – 512e and 4K Native. They go into much more detail on the blog.. Basically they have addressed the following issues..
- Introduce new and enhance existing API to better enable applications to query for the physical sector size of a disk
- Enhancing large-sector awareness within the NTFS file system, including ensuring appropriate sector padding when performing extending writes (writing to the end of the file)
- Incorporating large-sector awareness in the new VHDx file format used by Hyper-V to fully support both types of AF disks
- Enhancing the Windows boot code to work correctly when booting from 4K native disks