File system in Windows® 7
Windows 7 has turned off Windows Disk Defragmenter in order to take advantage of the capabilities and unique performance characteristics of solid-state drives (SSD). Disk Defragmenter is a computer program, its purpose is to optimize the time taken to read and write files to/from the disk by minimizing head travel time and maximizing the transfer rate. SSDs can write 4KB blocks at a time, but due to hardware limitations, they must delete larger blocks. Since the drive does not know which blocks are truly in use by its file system, each block of data written to the drive requires an additional write due to the moved block, this is the reason that some of the SSDs will move data around to exercise all of the blocks in the drive more evenly.
Windows 7 will also format a partition on a SSD differently from a mechanical hard disk drive. Windows 7 will make use of the new SSD TRIM command to physically erase logically deleted data, so that it won't need to be done later when new data is written to the same block. TRIM command allows the operating system to pass the information on down to the SSD controller. It allows an operating system to tell a solid-state drive (SSD) which data blocks are no longer in use.
Virtual hard disks (VHD) is a file which is structurally identical to a physical Hard Disk Drive. It allows multiple operating systems to reside on a single host machine. Its files can be mounted as drives, created, and booted from, in the same way as WIM files. Besides that, Windows 7 can be booted and run from a VHD drive. It can move files between a VHD and the host file system, it can do backup and recovery, it can do image management and patching and so on.
Removable Media features are also enhanced in Windows 7. Its features include the retaining of the ports for future use without rebooting and the ability to eject just one camera card at the same time. BitLocker provides encryption support to removable disks such as USB drives, these devices can be protected by a passphrase, and with a recovery key.
Microsoft has developed the Windows Imaging Format (WIM), a file-based disk image format. This format was used as a part of the installation procedure. This also works equally well with legacy versions of Windows. A system virtual machine provides a complete system platform which supports the execution of a complete operating system. An important characteristic of a virtual machine is that the software running inside is limited to the resources and abstractions provided by the virtual machine it cannot break out of its virtual world. In contrast, a process virtual machine is designed to run a single program, which means that it supports a single process. The main advantages of it is that it has capability to provide an instruction set architecture that is somewhat different from the real machine, because of its multiple operating system environments can co-exist on the same computer, but isolated from each other.
In a nutshell, users will get benefitted from the new and exciting features of file system present in Windows 7.