What is defragmentation? What does it mean when your hard drive is “fragmented”, or “needs defragging”? This is one of the services Trystal Tech offers as part of our Computer Performance Tweaking package, and we’ll give you an overview of how it works.

Every time you create a new document, download or install new software, or copy files and photos, the computer writes that data to the hard drive. It will start by writing those bits of data in order, so that they can be accessed all at once. However, over time, different parts of the files will need to be saved to different parts of the hard drive, and therefore the file becomes “fragmented”.

Here’s a very simple example. Say you have two files, file X with data XXXX and file Y with data YYYY. When you save file X, your hard drive will look like this:

XXXX

Now you create file Y, and your computer will store it just after file X:

XXXXYYYY

But now you want to add some more data to file X. Since the second file has taken up the space directly after file X, it will need to find somewhere else to put the new data. So now your harddrive looks like this:

XXXXYYYYXX

File X has become “fragmented”, meaning that pieces of it are split into different areas of the hard drive.
When you “defrag” your harddrive, you are re-organising each file so that it is stored as a complete item. After defragmentation, our example harddrive will look like this:

XXXXXXYYYY

So why does fragmentation affect computer performance? When you open a file, the computer must find all of the parts of that file first, so performance suffers if the file is scattered into several different places. In addition, file fragments can block up access to free space on the drive, causing your hard drive to appear more full than it actually is.

The picture on the right shows the fragmentation status of one of our client’s hard drives. This particular drive is extremely fragmented, at 58%. Just at a glance, you can see that the red squares occupy most of the hard drive, and these indicate fragmented areas. A healthy, defragmented drive would show mostly blue squares, and little, if any, red squares.

If you find your computer running slow, checking the fragmentation level of the drive is a good idea. For more information, check out our Computer Performance Tweaking package, or contact us.