X-bit labs

Mission "Defragmentation". Part 2: PerfectDisk

Category: Storage

by Aleksey Meyev

[ 08/09/2007 | 01:01 PM ]

This time we are going to check out defragmentation using one of the third-party software applications. We are going to compare the hard disk drives in PerfectDisk 8.0 from Raxco Software. We will also look at how the per-platter data density and the size of the cache-buffer affect the defragmentation efficiency.

Table of contents:

• Testing Methodology
  
• Tested HDDs
  
• Defragmentation without NCQ
  
• Defragmentation with NCQ
  
• Conclusion
  

In our previous article devoted to hard disk drives tests with the defragmentation tool built into the Windows XP OS we promised to return to this topic again. This time we are going to check out defragmentation using one of the third-party software applications. We are going to compare the hard disk drives in PerfectDisk 8.0 from Raxco Software.

Before we start, let’s recall what file fragmentation actually is and why we always try to avoid it. When saved to the hard disk, files are not always written into contiguous clusters. More often than not, they occupy a few strings of adjacent clusters in different parts of the platter. This occurs when a file stored on the hard disk gets larger after your processing it or when large files are written into an almost full hard disk when there is no string of free adjacent clusters on the disk to save the current file. As a consequence, the reading of a file like this takes longer since the HDD has to move its heads a longer way to collect the file fragments from the platters. So, the more fragmented your files are, the slower your PC works. It is file fragmentation that affects how fast the new game levels are being loaded and how quickly heavy applications start.

Programs called defragmenters are your main weapon against file fragmentation. All of them create a file distribution map over clusters. Then, each program uses its own algorithm to move fragmented files into free disk space so that each file occupies adjacent clusters. Various programs like that differ by special “skills” and features, such as the ability to defragment service files of the operating system (file allocation table, paging file, standby file), performance, resource consumptions, ability to work with a few storage devices at a time, defragmentation management options.

The PerfectDisk 8.0 program that we picked for our today’s tests following our readers’ recommendations can be considered one of the most advanced tools. Besides the above mentioned service files defragmentation, it also knows to defragment NTFS meta-data, combines all the free space on the hard disk drive into largest possible blocks of adjacent clusters, supports fully functional management from the command prompt, and requires only 5% of the hard disk drive free space to operate. The latter feature makes its positively different from the defragmentation tool built into the Windows XP, for instance, which requires at least 15% of the hard disk drive storage capacity to be free for proper operation. This feature will definitely be very important for those users who are forced to use up almost entire storage capacity of their hard disk drives.