What is Disk Defragmentation?

People of the older and middle generations, the now riddled disk drives (for floppy disks - floppy disks) and the first hard drives, know very well what defragmentation of a disk is and why this operation is necessary. If you do not control the performance, then you could very quickly get a faulty system. Take at least hard disks, which had to be reformatted from time to time, otherwise, due to thermal expansion and displacement of reading heads relative to sectors, you could receive a read error message. In addition, defragmenting the hard drive was just as necessary as monitoring the free space.

Since then, a lot of time has passed, and most of the "childhood diseases" have been eliminated. In addition, progress, taking the course to automate the work of components under the motto "Minimum user intervention," hid from computer owners ways to increase performance without the need to purchase new products. For example, many already realize that at the present time the "hard disk" of the entire computer is a hard disk. It's not for nothing that interest in storage devices based on solid-state memory is so high. However, few people know that there is a way to increase the performance of the hard drive used. To do this, defragment the disk. Actually, for this purpose, such an opportunity was developed. To understand the mechanism, it is necessary to recall the device of the hard disk itself.

Inside the body, on a common spindle rotated by an electric motor with a constant angular velocity, there are several disks with a magnetizable surface. During operation, the block of reading (recording) heads flies on the thinnest air cushion above (under) the discs. When the controller command, the heads are positioned at the required radius, then, according to the file table, the information bit is written / read to the desired disk / side region. How is disk defragmentation related to all of the above? Directly! It follows from the physical device of the hard drive that, with the spindle rotating at a constant speed, the read speed at the outer radii of the disks is much higher than on the smaller internal ones.

Now consider the program part. When initially formatting the hard drive, some users pay attention to the "cluster size" item. Its presence suggests that data on the hard disk is written not by a continuous stream, but by blocks. A special dispatcher program, in accordance with the file allocation table, records new information on free areas. It would seem - disk defragmentation is not needed! This is partly true, but only on the condition that the data already written on the hard drive will never be deleted. Then the new blocks will simply be added to the already existing ones - the perfect order! But since it is necessary to erase something from the disk, and something to add to it, there is often a situation where the recording of blocks of a single file (for example, a movie) is performed not consistently, but in the released areas. As a result, the data of the file is spread out across the entire disk (fragmented). The user may not even know about this, but the speed of working with such a file is significantly reduced. Sometimes a disk map is all in "holes", and the dispatcher has to write down the principle "there is a little - here a little bit". To solve this problem, you can use the standard utility: My computer - Disk (Properties) - Tools - Defragmentation. As an option - work with third-party programs, as their capabilities are richer.

By the way, what is disk defragmentation , Windows 7 "knows" very well, so by default it executes it on a schedule. Such programs not only optimally place files, removing "holes", but also move the most requested data to the external radii of disks.