Optimization Pros and Cons

---

In addition to increasing system performance, optimization is said to reduce the potential for file fragmentation over time. Where optimization does appear to add a small amount of value is in the individual desktop. Particularly in cases where the same types of files are accessed repeatedly while others are left dormant for long periods, optimization may reduce head movement. When the user is using the computer for only a couple of functions, such as browsing and word processing, optimization's reliance on access patterns may offer some potential benefit.

For the more sophisticated user, especially for the typical network, optimization is not likely to provide much return. A Microsoft program manager, who for many years was responsible for remote and distributed file systems as well as storage management on Windows enterprise systems, told me that the simpler the disk I/O model, the better analysis you can make for some type of improvement in performance from optimization. But, when you start moving to RAID and enterprise environments, disk optimization becomes very shaky. This opinion is shared by the National Software Testing Lab (NSTL), which reported on their investigations of both defragmentation and optimization. The NSTL paper states that file positioning is equally as likely to worsen system performance as to improve it. NSTL believes that even if the two conditions balance out at zero, the overhead involved can result in a net loss. (Note: The NSTL's Final Report on Defragmentation Performance Testing is available at http://www.execsoft, and the complete text of the NSTL white paper quoted in this chapter, System Performance and File Fragmentation in Windows NT, is also available at http://www.execsoft.com.)

---