Monday, December 26, 2005

Computer: Testing drive compression on Windows XP

Dec 26, 2005:

I am testing drive compression on my new Hitachi hard drive. At this moment, I found that it works quite well and very efficiently.

I copy 2.53GB of data from my trusty Maxtor to the new Hitachi drives. The size on the uncompressed Maxtor drive is 2.57GB (Figure 1), but the size on the compressed Hitachi drive is only 2.22GB (Figure 2). The side effect is the cost for CPU overhead. During copying, CPU usage is virtually 100%. The drive with compression will be shown with blue label, while the common ones are in the block label (See figure 3).

Figure 1. Size on uncompressed volume is 2.57GB, which is larger than the size of data.

Figure 2. Size on compressed volume, which is smaller than the size of data.

Figure 3. Label of a compressed volume is blue, while others are black.

Experiment about copying time was conducted too. I copied about 2.53 GB of data from an USB uncompressed hard drive to a Firewire hard drive. The Firewire drive was uncompressed for the first phase of copying experiment. Then the same Firewire drive was compressed to perform the second phase of copying experiment. The first phase of copying finished in 5:01 minutes, while the second phase spended up to 6:29 minutes. The space was saved by 13.6%, but writing time increased by 29.2%. This implies that for the test data, it is not a big deal to use compressed volume to save disk space unless we are really run out of space.

I may stop using this feature if I am going to use the new hard drive as a main one. At this point, I am testing the new drive, along with its Firewire interface, to find if the new solution is reliable, but is faster than my old solution. A faster hard drive, will be the main one, and the slower one will be a backup one.

No comments: