Tuesday 14 December 2010

Speedup Your HDD With Raid


If one fast drive is good, then five working together is surely better.
Redundant Array of Inexpensive Disks (RAID) technology has been a significant lifesaver and performance boost for file servers. RAID can be set up in different configurations to provide systems with fault-tolerance or performance enhancements that are crucial to keeping data safe. It can be applied to personal desktop systems to provide significant disk drive performance enhancement.

RAID-0 (zero) is the most basic and highest performing RAID configuration. Portions of data normally stored on one disk drive are spread out across multiple drives, and those drives are accessed in parallel to deliver the data faster, because each drive does not have to access all of the data before it can be delivered. RAID-0 is unfortunately and by nature the least reliable in terms of data integrity, because a failure in any single drive renders all of the data useless.

In contrast to RAID-0, in a RAID-1 configuration all of the data is stored equally on two drives, in parallel. This slows the storage and reading performance but almost guarantees that the data remains intact even if one of the drives fails.

RAID-5
is somewhat a mix of RAID-0 and RAID-1, striping data across multiple drives but also adding error correction information across the drives, providing the advantages of parallel drives and a high degree of ability to recover data if one drive should fail.

Another hybrid implementation of RAID that is very affordable and intended for desktop system is RAID-0+1. The Promise Technology (http://www.promise.com) FastTrak TX4000 RAID controller card is specifically meant for desktop users with an appetite for high-performance disk systems. Performance enhancements of up to 30% are possible. Upgrading with top-performing disk drives and putting them into a RAID configuration just might knock the dust bunnies out of your keyboard.

The basic steps to install a RAID configuration on your PC are listed below. Be aware that the specific steps will be unique to the RAID controller (system board or add-in card type), your system BIOS, and RAID configuration software. After installation, the RAID configuration should appear to your operating system as a single-disk volume.

You need a RAID controller or RAID capabilities built into your system board. Promise Technologies is one of the most popular brands of add-in RAID controllers for IDE drives.

Have at least two identical disk drives on hand for RAID-0 and 1. Configuration of a simple RAID is a lot easier if the drives are identical: there will be no wasted space, and they should mirror each other and perform equally well. RAID 0+1 will require at least four disks.

If necessary, make a bootable DOS diskette with any necessary drivers or configuration program for your RAID controller. For BIOS-based RAID setups, familiarize yourself with the RAID setup screens and options in BIOS. It is likely you will have to connect the RAID drives to different IDE connections than the normal non-RAID IDE interfaces.

With the system powered down, install and connect the drives to the RAID controller interface connectors.

Start the system and either boot with the DOS diskette containing the RAID controller configuration program or get into the BIOS setup to access the RAID configuration screens.

Select the type of RAID you will be creating—typically 0, 1, or 0+1.

Partition the drives with the configuration program or BIOS screens. This process establishes how the RAID controller views and uses the drives.

When RAID controller configuration and disk partitioning is complete, you will either FORMAT the drives under DOS or start the installation of your operating system onto the new RAID system as the primary boot drive.

(RAID 1 and higher only) To test your configuration after installing your operating system, shut down and disconnect one of the RAID drives, then restart to verify that indeed the RAID system actually mirrors data to one of the drives.

No comments:

Post a Comment