Calculate Your Space

So, you've decided to set up a Matrix RAID array but you might not have a clue about the kind of capacity you would get. For RAID 0 and RAID 1 arrays, it's fairly simple to calculate the capacity using the formula below.

RAID 0
n x s = S (total array size)
n = number of hard disk in array
s = size of smallest hard disk in the array

RAID 1
s = S total array size
s = size of smallest hard disk in the array

However, Matrix RAID is a little bit different as it allows you to create both RAID 0 and RAID 1 volumes on the same hard disk. Thus, the sizes you determine for each array will determine the final size you have.

The easiest way to determine the final size is by first determining the size of the RAID 1 volume. Then, you will know how much you have left for your RAID 0 volume.

So, let's say we want to create a Matrix RAID array using two 80GB hard disks, with 30GB reserved for critical data in a RAID 1 volume.

You will, therefore, need to use 30GB on both hard disks to create a single 30GB RAID 1 volume. That leaves 50GB on each hard disk which can then turned into a 100GB RAID 0 volume. The final capacity for this Matrix RAID array will therefore be 130GB, out of a physical capacity of 160GB.

But if you only need 10GB for a RAID 1 volume, then the final capacity for your Matrix RAID array will be 10GB + 140GB = 150GB.

Some Setup Tips

After knowing what volume sizes you want for your Matrix RAID array, it's time to create them. Here are a few tips that you can use to setup your RAID volumes.

First of all, you should create your RAID 0 volume before you create your RAID 1 volume. By doing it so, you will make sure that the RAID 0 volume gets the inner tracks of both hard disks. You will want it to be using the inner tracks because that is where the disk transfer rate is the fastest. And RAID 0 is all about speed alone. In fact, this is the volume where you will want to run your applications, paging files and scratch files on.

And once you setup your RAID 0 array, you can setup the RAID 1 array with the remaining space.

Next, since data performance is far more important than data redundancy, my advice would be to setup just enough space for your critical data. But what you consider critical is entirely open to interpretation.

However, operating system installations, program files, etc. should not be considered as critical as they can always be reinstalled. Also in my opinion, media files like MP3 files, downloaded video clips also don't qualify as critical data. Such files may be stored in the RAID 0 volume for improved performance.

Instead, files and folders like the My Documents folder, family photos and videos, e-mails, databases, etc. should be considered critical and stored in the RAID 1 volume. There simply isn't any golden rule of the thumb or formula to determine the size of your RAID 1 volume. It simply depends on the volume of much critical data you have.

A simple calculation may be to find out how much space your current critical data takes up to, and multiple that by two to ensure there's room to "grow". That's how I've been partitioning my system.

Well, I hope that helps you optimize your Matrix RAID setup!