File Systems

On very large disks, the maximum size of a volume or file and the maximum number of files per volume depend on the file system used to format the volume.

Note

Windows 2000 can combine noncontiguous disk areas when creating volume sets and stripe sets, but these volumes have the same maximum size limitations of a single volume.

Maximum Sizes on FAT16 Volumes

FAT16 can support a maximum of 65,524 clusters per volume. Table 17.3 lists FAT16 size limits.

Important

For Windows NT and Windows 2000, the cluster size of FAT16 volumes from 2 GB through 4 GB is 64 KB, which can create compatibility issues with some applications. For example, setup programs do not compute volume free space properly on a volume with 64 KB clusters and cannot run because of a perceived lack of free space. For this reason, either NTFS or FAT32 must be used on volumes larger than 2 GB. The Format tool in Windows 2000 displays a warning and asks for a confirmation before formatting a volume with 64 KB clusters.

Table 17.3 FAT16 Size Limits

Maximum Sizes on FAT32 Volumes

A FAT32 volume must have a minimum of 65,527 clusters. The maximum number of clusters that Windows 2000 can mount on a FAT32 volume is 4,177,918. Windows 2000 can format volumes up to 32 GB, but it can use larger volumes created by other operating systems. Table 17.4 lists FAT32 size limits.

Table 17.4 FAT32 Size Limits

Maximum Sizes on NTFS Volumes

In theory, the maximum NTFS volume size is 2 64 clusters. However, there are limitations to the maximum size of a volume, such as volume tables. By industry standards, volume tables are limited to 2 32 sectors.

Sector size, another limitation, is typically 512 bytes. While sector sizes might increase in the future, the current size puts a limit on a single volume of 2 terabytes (2 32 * 512 bytes, or 2 41 bytes). For now, 2 terabytes is considered the practical limit for both physical and logical volumes using NTFS.

Table 17.5 lists NTFS size limits.

Table 17.5 NTFS Size Limits