This week, my series on home computer upgrades continues. Last column I talked about computer memory types, and this week I continue with practical information on maintaining your hard disk. Often, people choose to upgrade a computer because they have run out of storage space. New hard drives are more economical than ever, and with some basic knowledge they can be easily installed by a home user. However, buying a new hard drive should not be your first step when a drive gets slow and storage space becomes limited. Some simple drive maintenance may solve your problem, and help you to understand why hard disks slow down over time.
Many things can slow down your hard drive. For example, a fragmented drive and a drive over eighty percent full will be slower. Practicing regular drive maintenance can ensure that your drive does not become excessively fragmented and keep it running well. Understanding why this is so is easier if you understand how hard drives store your data.
Every hard drive is divided in to sections called clusters. These clusters can vary in size from drive to drive based on drive size and drive format. There are three file storage formats for a drive: FAT16, FAT32 and NTFS. FAT16 drives are used by DOS, Windows 3.x, 95, 98, and ME. FAT32 drives are used by Windows 95 SR2, 98 and ME, and NTFS drives are formatted through Windows NT, 2K and XP. These charts show how cluster sizes differ between drives.
DOS Cluster sizes
Drive size — Cluster Size
127mb — 2kb
255mb — 4kb
512mb — 8kb
1gb — 16kb
2gb — 32kb
4gb — 64kb
FAT32 Cluster Sizes
Drive Size — Cluster Size
< 512 -- not supported 8gb -- 4kb 16gb -- 8kb 32gb -- 16kb 2000gb -- 32kb NTFS Cluster Sizes
Drive Size — Cluster Size
512mb — .5kb
1gb — 1kb
2gb — 2kb
2gb+ — 4gb
One thing to keep in mind — the drive size doesn’t mean the physical size of it. It refers to the partition size. One hard drive can be divided into 2 or more drives. My wife’s first laptop had one actual drive, but it was divided into 2, drives C and D. Drive C had the operating system and personal space drive D had a bunch of manufacturer items. The making of two or more drives from one hard drive is called a partitioning. So the cluster size depends on the size of the partition.
Why is cluster size important? Because when your computer stores a file on the drive it will always start writing the data on the next free cluster, even if some clusters are not entirely full.
Let’s look at an 8kb file saved on a 4GB drive using the three file formats. In FAT16 a 8kb file would occupy 64kb of space (one full cluster); in FAT32, 8kb of space; and in NTFS, also 8kb of space. So FAT16 would waste 56kb of hard drive space. Over time that can really add up. On FAT32 and NTFS little or no space is wasted for a file of this size.
Comparing FAT32 and NTFS cluster sizes using a 15kb file and 50gb hard drive results in 17 wasted kb on FAT32 and only 3 wasted kb on NTFS.
DRIVE WRITING 101
When one stores data or installs a program on a drive, the computer finds the first available cluster and starts writing to the disk. A visual example of how files are stored can be shown with a string of letters, where each letter represents a new file: hhhddrkkkkkkkkkqqsssssss
Now, if you delete file d and q then store file z which is larger than d and q the new file will occupy the clusters that were made free when the smaller files were removed first. You’ll get something like this: hhhzzrkkkkkkkkkzzssssssszzzzz
You can see that file z is split up and stored in different locations on the drive. Hence, file z is fragmented. A fragmented file takes longer to find than a non-fragmented file. Your computer won’t have much trouble with a little fragmentation, which is inevitable, but over time your computer can really slow down.
So how do we fix this problem? There are programs that will help defragment our files. Windows has a tool (called Disk Defragmenter. Under Windows XP it’s in your System 32 folder and it can be scheduled through the Control Panel to run on a regular schedule automatically), and companies like Symantic and Diskeeper have created utilities as well. These programs find the files that are fragmented and gather all the pieces. It moves them to a space that can fit the entire file and then fill its old space(s) with other files. Eg; hhhrkkkkkkkkkssssssszzzzzzzzz. You must have some space free on your drive so that the files can be moved around and if you have not defragged in a long time, it can take quite a while. Running Defragmenter regularly will make the task quicker.
Another problem is that on occasion the computer loses track of what clusters are available. It thinks more clusters are in use. The user might not notice a problem arising from this, but it makes the improperly tagged cluster unusable. These lost clusters are created when the writing process is interrupted, like shutting off your computer before it is finished writing its closing data. Like disk defragging windows also provides a utility to fix these lost clusters. Windows calls it Scan Disk while Symantec calls theirs Disk Doctor.
The last bit of drive maintenance concerns bad disks. For anyone who’s used floppy disks regularly, they have probably lost files on the disk because the computer can no longer read the disk. Disks and disk drives are very picky items because a fingerprint or the tiniest scratch can ruin a portion of the disk. When running scandisk, or whatever your tool is, you should have an option to do a surface test or its equivalent. A surface test checks the surface for abnormalities and marks them “bad” if it can’t read a spot. If I find a bad spot on a floppy disk, I throw it out. I find one bad spot leads to another. They can multiply like rabbits. I have never personally found one on my hard drive. One tip, doing large drives can take a loooooooooong time to do a surface test. At home I have two 100GB drives. It takes 9 hours 45 minutes to surface test EACH drive. Doing the math, it’s about 1 hour per 10GB.
Keeping your drive under 80% full by deleting unwanted or unneeded files and regular disk checking can keep drives healthy, clean and fast.
LIST OF TERMS
FAT – File Allocation Table – a file the computer uses to keep track of where all of your files are stored.
NTFS – NT File System
WINDOWS TIP OF THE WEEK
When you right-click on a file on your computer, you see a menu including a list of “SEND TO” options that allow you to send your file to a number of locations or programs. Do you ever wish that you could create your own SEND TO options? Well you can.
Run Windows Explorer.
Select your Windows directory (C:\Windows for example).
If you’re running Windows 95, 98, or ME, select “Send To” folder.
If you’re running Windows NT/XP, select “Profiles\Default User\Send To” folder.
Now, simply create shortcuts inside the Send To folder as usual to the devices and programs you want to have access to from the “Send To” menu.
For example, to add your WORK folder on your zip drive (D:\Work) to the Send To menu:
Right click inside the Send To folder and select “New | Shortcut”
Type “D:\Work” (without quotes) and click on “Next”
Type a name for the newly created Send To item (“My Work Folder” for example) and click on “Finish”
Now when you right-click on files, you’ll see “My Work Folder” appear as an option in the Send To menu.
COOL SITE OF THE WEEK
To download a real time view of the earth from any view point and see the latest earthquake information on your desktop as a background go to: http://www.hewgill.com/xearth/
If you have any questions or suggestions for topics you want discussed please email me c/o The Voice.
The Voice accepts no responsibility for loss of data or any other computer related problem you might encounter as a result of following computer advice in this or any other column. The tip of the week is intended to help you personalize your computer system. Novice users should ensure they understand the directions, and make backups of any files changed.