Implementation
Software RAM drives use the normal RAM in main memory as if it were a partition on a hard drive rather than actually accessing the data bus normally used for secondary storage. Though RAM drives can often be supported directly from the operating system via special mechanisms in the operating system kernel, it is possible to also create and manage a RAM drive by way of a user space application process. Usually no battery backup is needed due to the temporary nature of the information stored in the RAM drive, but an uninterruptible power supply can keep the entire system running during a power outage, if necessary.
Some RAM drives use a compressed filesystem such as cramfs to allow compressed data to be accessed on the fly, without uncompressing it first. This is convenient because RAM drives are often small due to the higher price per byte than conventional hard drive storage.
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