RAM DRIVES

4/25/98

RAM Drive: A RAM drive is a portion of memory that is configured to look like a disk drive to application software. RAM drives were widely used in early PCs to speed up access to floppy disks and slow hard drives. In particular they were often used to store temporary working files that are constantly being read and written. RAM drives can be orders of magnitude faster than physical disk drives.

Since about 1990, the use of RAM drives has decreased. They are relatively hard to configure and often require a great deal of tuning for specific applications. They have been replaced by disk caches in memory that store recently used information in memory. However, in specific cases, RAM drives can still be used to enhance the performance of specific applications since they can be set up to store only files that are known to be needed. Since disk caches decide what to retain in memory on the basis of general principles rather than specific knowledge, there will always be cases where a RAM drive can be used to retain data in fast memory that a cache would push to much slower disk.

RAM drives require specific software that provides/emulates operating system file systems. They get a drive designator, and respond to most normal disk commands.

RAM drive drivers are available for many popular OSes.

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