RamDisk and RamDisk Plus™ create a virtual disk from the server's system memory (RAM). Although in many respects the virtual disk behaves like a physical hard disk, in two key areas it does not: it is much, much faster, and its contents are lost when the server stops. Like a physical disk, a RAM disk is of a set size, is assigned a drive letter, may contain a file system (including NTFS with compression), and can be accessed by Windows Explorer and other applications. Files can be copied and moved to and from it, and deleted from it. And it can be shared, so it can be accessed by other computers on a network.
Speed: Perhaps the primary reason for using a RAM disk as opposed to a physical disk is speed. The average time required for a disk drive to move its magnetic heads over the spinning disks and then wait for the correct sectors to arrive under them is typically measured in milliseconds. Because of this, the random I/O performance of an average IDE drive may attain to 10 MB/s throughputs, of a SCSI drive 15 MB/s, and of a high performance RAID 5 storage subsystem 50 MB/s.
In contrast, RamDisk's throughput can reach 1 GB/s or more, depending on the server's processors, memory, memory-bus bandwidth and hardware implementation. Servers with high-performance processor and memory subsystems and low-cost storage subsystems can realize dramatic disk I/O throughput improvements using RamDisk or RamDisk Plus.
Security: Another reason for using RamDisk is security or privacy. Once the server is restarted or shutdown, the contents of the RAM disk is lost. For some services or applications, this is an important attribute that contributes to the protection of sensitive data or information.
Risk: However, this same attribute places data at risk of loss in the case of a system crash or power loss. An attached Uninterruptible Power Supply (UPS) can reduce the risk of loss but not eliminate it. For lowest-risk solutions see SuperVolume and SuperCache.
Minimum System Requirements for RamDisk
Windows 2000 - all server editions
Windows Server 2003 - all editions, 32- and 64-bit (x64 and Itanium-based)