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SuperTrak66™ User's Manual 
Chapter 6 
 
- 103 - 
6.1 Application Scenarios 
This section describes typical application scenarios for a RAID system. You may 
use this information as a guideline to tailor your RAID system configuration to meet 
your specific needs.  
 
Keep in mind that when dealing with striped arrays, a larger stripe block size 
typically benefits arrays that tend to receive more random/smaller I/O requests. 
This is because such a setting tends to minimize seeks for a small request down 
to a single I/O operation. In contrast, a small stripe block size setting typically 
benefits arrays which tend to receive more sequential/larger I/O requests. This is 
because such a setting maximizes throughput by employing the data transfers of 
all drives simultaneously. 
 
NOTE: Though the following configurations recommend different RAID levels, 
RAID 3 is recommended in most single-threaded (non-server) desktop PC 
operations. 
High Performance Desktop PCs Working With Large Files 
For video editing or desktop publishing PC stations where large files are stored on 
the hard drive, the need for performance outweighs that of data security. Accessing 
such large files requires sequential data transfers where performance can be 
improved by using striping (RAID Level 0). An ideal setup would have the large data 
files stored on the striped array, and the operating system boot drive using a 
separate disk controller (i.e. onboard motherboard controller).  
 
When defining such an array, remember that a small stripe block size (such as 
64KB) typically benefits arrays which tend to receive more sequential/large I/O 
requests (such as those used in video editing) since it maximizes throughput by 
employing the transfer of all drives simultaneously. The more drives assigned to 
this array, the better the throughput potential will be. Bear in mind, there are no 
fault tolerant data protection features provided in a RAID 0 array. It is exclusively 
geared towards gaining data transfer performance. 
Corporate Desktop PC Requiring Data Protection 
Under Windows NT, users have the option of enabling fault tolerance through 
software. SuperTrak66 permits a bootable, hardware-based fault tolerant solution to 
secure data from drive failure. RAID Level 3 offers the largest data capacity while 
maintaining fault tolerance using parity information. RAID 0+1 is also 
recommended since it offers higher data throughput and dual fault tolerance though 
it is more expensive in terms of drives. 
Windows NT File Server 
Windows NT tends to work heavily with large swap files for virtual memory. Under 
such a heavy load, the swap file I/Os undergo intensive activity. If the user's data 
files and the system files are located on the same drive, then the system 
performance is typically degraded because of the swap files.