HSG80 ACS Solution Software V8.6 for Windows NT and Windows 2000 Installation and Configuration Guide

2–10 HSG80 ACS Solution Software Version 8.6 for Windows NT and Windows 2000 Installation and
Configuration Guide
Figure 2–7. Mapping a unit to physical disk drives
Determining Storage Requirements
It is important to determine your storage requirements. Here are a few of the questions you
should ask yourself regarding the subsystem usage:
■ What applications or user groups will access the subsystem? How much capacity do
they need?
■ What are the I/O requirements? If an application is data transfer-intensive, what is the
required transfer rate? If it is I/O request-intensive, what is the required response time?
What is the read/write ratio for a typical request?
■ Are most I/O requests directed to a small percentage of the disk drives? Do you want
to keep it that way or balance the I/O load?
■ Do you store mission-critical data? Is availability the highest priority or would
standard backup procedures suffice?
D100
RAID1
Disk 10000 Disk 20000 Disk 30000
Storageset
name
Host addressable
unit number
Controller
PTL addresses
CXO6186B