HP StorageWorks HSG80 ACS Solution Software V8.8 for Windows NT, Windows 2000, and Windows Server 2003 (32-bit) Installation and Configuration Guide (AA-RV1XA-TE, March 2005)

Planning Storage Configurations
79HSG80 ACS Solution Software V8.8 for Windows NT, Windows 2000, and Windows Server
2003 (32-bit) Installation and Configuration Guide
For example, in a three-member stripeset that contains disk drives Disk 10000,
Disk 20000, and Disk 10100, the first chunk of an I/O request is written to Disk
10000, the second to Disk 20000, the third to Disk 10100, the fourth to Disk
10000, until all of the data has been written to the drives (Figure 24).
Figure 24: Three-member RAID 0 stripeset (example 1)
The relationship between the chunk size and the average request size determines if
striping maximizes the request rate or the data-transfer rate. You can set the chunk
size or use the default setting (see “Chunk Size” on page 91, for information about
setting the chunk size). Figure 25 shows another example of a three-member
RAID 0 stripeset.
A major benefit of striping is that it balances the I/O load across all of the disk
drives in the storageset. This can increase the subsystem performance by
eliminating the hot spots (high localities of reference) that occur when frequently
accessed data becomes concentrated on a single disk drive.
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