IDE Training Course, Part 2: Performance and Data Security with RAID

Wanted: More Capacity

The single most efficient way to effectively expand system memory is to use several hard drives. Often it's enough to install an additional hard drive in order to give performance a bit of a boost. Then you can move the bandwidth-hogging Windows swap file (the so-called virtual memory) to the second drive, so that system files can be accessed independently. Furthermore, using applications like Photoshop is really only comfortable if the swap file is not located in the system partition.

Of course, the more elegant and truly performance-boosting method for all application areas is to set up a hard drive array in RAID mode. Here, the existing hard drives are not run independently, but are managed by the RAID controller and described according to a predefined schema.

So How Does A RAID Array Work?

The array itself is set up in BIOS of the RAID controller by adding all of the installed hard drives to be part of the array. Depending on the controller, the block size and the total capacity, initialization may take up to several hours. The selection of the block size deserves special attention. Large blocks ensure maximum data transfer performance, but for mostly small files (smaller than the size of a block), an annoying amount of memory is wasted. Hence a block with 64 kB will always need at least those 64 kB - even if the information to be written is clearly of a smaller size.

After the operating system has booted, the new array has to be formatted. Performing a Quick Format under Windows takes no time at all, while the full format checks every single sector and in turn may take quite some time. After the system has rebooted, the RAID array is available under Windows as a new drive. Its use is no different from that of a single hard drive.