DiskLayout

DiskLayout is the organization of data on a storage device, including the physical arrangement of platters, tracks, and sectors on hard disks, as well as the logical organization of space through partitions and file systems. Understanding disk layout helps with performance, capacity planning, data recovery, and system boot.

In traditional hard disk drives, data is stored on magnetic platters with concentric tracks and sectors; modern HDDs use zone bit recording and caching. Solid-state drives replace mechanical geometry with units of erase blocks and pages under the flash translation layer, making the physical layout largely invisible to software but still affecting wear, performance, and endurance.

Disk layout also includes partitioning and the file system. Partitions divide a disk into independent volumes; partition tables such as MBR or GPT describe their locations. Within partitions, file systems (ext, NTFS, APFS, exFAT, etc.) define how files are stored, including metadata structures like inodes or the Master File Table, and how space is allocated (blocks, clusters, extents).

Boot sectors and system partitions are part of disk layout, with MBR or GPT/UEFI standards determining how a computer starts. Logical volume managers and RAID configurations add additional layers that present a single logical disk to the OS.

Performance depends on layout choices; fragmentation is a concern for HDDs, while SSDs rely on TRIM and wear leveling. Partition resizing, filesystem checks, backups, and encryption can affect and be affected by disk layout.