Disk Size Manager 

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Wasted Space

Disk space for files storage is allocated by clusters – space sections of fixed size. If the file’s size is not exactly equal to some whole number of clusters, the last cluster allocated for the file is not completely filled with the file’s contents; there is some free unused space left. These remains form the wasted space of the disk.

Thus, here is the formula you should remember: allocated space = file(s) size + wasted space

Depending on the disk partition size and the type of its file system clusters of different size are used. For example, Windows 9x with its file system FAT/FAT32 may have very large cluster sizes:

A huge number of small files stored on the disk significantly increase the amount of wasted space on FAT partitions.

Assume the situation: you have a single FAT32 partition on a 32GB hard disk. According to the table above you have a cluster size of 32KB on it. If you store 10 files of 1 KB each on this partition, the total amount of 10*32KB=320KB would be allocated for them. At that only 10 KB would be used for your good; the rest – 310KB –would be wasted.

There are the following ways for reducing the wasted disk space:

·    Make smaller partitions. Try to avoid partitions larger than 16GB on a FAT32 drive.

Pitfall: smaller partitions will increase the number of drive letters.

·    Try the NTFS file system (available for Windows NT/2000/XP). The NTFS usually operates with small (512 - 4096 Byte) clusters and provides the most efficient data storage of all Windows file systems. NTFS is also able to compress selected directory branches.

Pitfall: NTFS partitions cannot be accessed from Windows 9x for DOS without use of 3rd party software.