SmartDrive
SmartDrive (or SMARTDRV) was a disk caching program that shipped with MS-DOS versions 4.01 through 6.22 and Windows 3.x.[1] It improved disk transfer rates by storing frequently accessed data in the main memory. Early versions of SmartDrive were loaded through a CONFIG.SYS device driver named SMARTDRV.SYS. Later versions were loaded through an executable file named SMARTDRV.EXE, usually automatically at boot time by including the SMARTDRV.EXE command in AUTOEXEC.BAT (or install=SMARTDRV.EXE into CONFIG.SYS), though it could still be loaded as a driver if double-buffering was required.
A cloaked variant of SmartDrive utilizing the Cloaking API was available from Helix Software. On 386 processors it could relocate and run in protected mode in order to reduce its DOS real-mode memory footprint.
The Windows 2000 and XP setup programs suggest that SmartDrive be used to decrease installation time when installing from MS-DOS.[2]
