Search results
Results from the WOW.Com Content Network
In computer file systems, a cluster (sometimes also called allocation unit or block) is a unit of disk space allocation for files and directories.To reduce the overhead of managing on-disk data structures, the filesystem does not allocate individual disk sectors by default, but contiguous groups of sectors, called clusters.
Due to typical file system design, the amount of space allocated for a file is usually larger than the size of the file's data – resulting in a relatively small amount of storage space for each file, called slack space or internal fragmentation, that is not available for other files but is not used for data in the file to which it belongs.
The terms partition table and partition map are similar terms and can be used interchangeably. The term is most commonly associated with the MBR partition table of a Master Boot Record (MBR) in PCs , but it may be used generically to refer to other formats that divide a disk drive into partitions, such as: GUID Partition Table (GPT), Apple ...
The gigabyte (/ ˈ ɡ ɪ ɡ ə b aɪ t, ˈ dʒ ɪ ɡ ə b aɪ t /) [1] is a multiple of the unit byte for digital information. The prefix giga means 10 9 in the International System of Units (SI). ). Therefore, one gigabyte is one billion by
Cylinder partition alignment, partitions starting on logical or physical cylinder boundaries on hard disk drives; SSD partition alignment, partitions starting on NVM boundaries (with typically 4 KB to 1 MB in LBAs size) on SSDs and other flash-based memory devices; RAID stripe alignment, partition alignment based on stripe boundaries
The protective MBR is stored at LBA 0, and the GPT header is in LBA 1, with a backup GPT header stored at the final LBA. The GPT header has a pointer to the partition table (Partition Entry Array), which is typically at LBA 2. Each entry on the partition table has a size of 128 bytes.
Support for partitioned media, and thereby the master boot record (MBR), was introduced with IBM PC DOS 2.0 in March 1983 in order to support the 10 MB hard disk of the then-new IBM Personal Computer XT, still using the FAT12 file system. The original version of the MBR was written by David Litton of IBM in June 1982.
Cylinder, head, and sector of a hard drive. Cylinder-head-sector (CHS) is an early method for giving addresses to each physical block of data on a hard disk drive.. It is a 3D-coordinate system made out of a vertical coordinate head, a horizontal (or radial) coordinate cylinder, and an angular coordinate sector.