In general, the larger cluster size you use, the fewer clusters the files will use, and then the faster the files are accessed by OS. What’s the importance of allocation unit size?Īs mentioned above, when the PC writes and reads data, the unit is cluster (not sector). And you can set a 4 K disk’s allocation unit size to smaller than 4 K (like 512 bytes, etc.).ģ. Therefore, the cluster size of 4 K hard drive is calculated in the unit of 512 bytes. The operating system can only see the logical sectors but can’t see the physical sectors. To be backward compatible with old host computer hardware and software components adopting 521-byte-sector disks, hard disk companies use technology to convert a physical 4 K sector into 8 logical 512-byte sectors. Nowadays, almost all hard drives on the market are 4 K hard drives. Starting from 2010, hard disk companies have gradually migrated sectors from the traditional size of 512 bytes to 4096 bytes. If the sector size of a disk is 512 bytes, the allocation unit size (cluster size) could be 512 bytes, 1024 bytes, 2048 bytes, 4096 bytes, 8192 bytes, 16384 bytes, etc. Therefore, allocation unit is the smallest logical data storage unit.Īs mentioned about, a cluster is composed of sectors.
Hence, the operating system will combine adjacent sectors to form an allocation unit (also called cluster), and then manage data in the unit of cluster (in the level of OS) to efficiently utilize resource. However, there are so many sectors on the hard drive that the operating system cannot address all of them. When a file is stored into hard drive, it will be divided into blocks to be stored in sectors.
In general, the sector size is fixed to 512 bytes or 4096 bytes (4 K).
But, what’s the functionality of the allocation unit size option? To figure out this, please read the following contents.ĭo you know the structure of hard disk? If you know about hard disk, you may know that sector is the smallest data reading and writing unit in disk level. When you create/format a partition, you are offered a window, allowing you to choose a file system and an allocation unit size, just like the following picture: How to Change FAT32 Allocation Unit Size.What Allocation Unit Size Should I Use for FAT32.Have you noticed allocation unit size when you create or format a partition? What is allocation unit size? What allocation unit size should you use for FAT32 partition? In this post, MiniTool Partition Wizard will talk about these problems, to help you choose a proper FAT32 allocation unit size.
0 kommentar(er)
