HPFS (High Performance File System)

HPFS (High Performance File System) is the file system introduced with IBM's OS/2 Version 1.2. HPFS is noted for handling large files (2 gigabytes) across multiple hard disk volumes (addressable up to 2 terabytes) and long file names (up to 256 bytes). HPFS was designed to get around several limitations at the time in MS-DOS, among them its eight-character name restriction. HPFS uses a centrally-located root directory and B-tree lookup to speed access. HPFS can coexist with the MS-DOS file system, File Allocation Table (FAT), or run independently.

Among the benefits of HPFS:

• Contiguous storage of extended attributes (without the EA DATA.SF file used by FAT)
• Resistance to file fragmentation
• Small cluster size
• Support for larger file storage devices (up to 512 GB)
• Speedier disk operation

Among the drawbacks:

• Requires more system memory
• HPFS partitions are not visible to MS-DOS, so if you need to boot from a floppy disk, it could be inconvenient.
• Native DOS needs a special utility (Partition Magic from PowerQuest) to access a HPFS partition