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c++coperating-systemdosfat

clusters, pages, sectors in FAT file system


Im trying to understand the concept of a "cluster" in a FAT filesystem. Specifically what is the relationship between a cluster, a Block, A Sector.

My understanding is the following 1) A Block/Page is 4096 bytes and a block is divided into sectors. 2) A sector is the smallest unit of storage on a disc. 3) Data us retrieved and stored in blocks/pages. 4) A disc has tracks and each track has Blocks/pages.

Is my understanding right? Im not sure where a cluster fits into all this.

Can someone clarify my understanding


Solution

  • Quoting from this link:http://cquirke.mvps.org/9x/fat.htm

    Cluster: Single unit of data storage at the FATxx file system logic level

    Sector: Single unit of storage at the physical disk level

    A cluster is the smallest unit of storage the operating system's file system can manage. For example, if a 1KB file is stored in a system with a 32KB cluster size (see table below), the 1KB file takes up 32KB of disk space. Below are the cluster sizes for the FAT32 file systems on Windows computers.

    Disk Size          Cluster size
    
    512MB-8GB           4KB
        8-16GB          8KB
       16-32GB         16KB
       32GB+           32KB