WebPAM User v1.5 - Promise Technology, Inc.
WebPAM User v1.5 - Promise Technology, Inc.
WebPAM User v1.5 - Promise Technology, Inc.
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Choosing a RAID Level<br />
95<br />
Chapter 6: <strong>Technology</strong> Background<br />
There are several issues to consider when choosing the RAID Level for your<br />
logical drive. The following discussion summarizes some advantages,<br />
disadvantages and applications for each choice.<br />
RAID 0<br />
Recommended Applications for RAID 0<br />
• Image Editing<br />
• Pre-Press Applications<br />
• Any application requiring high bandwidth<br />
RAID 1<br />
Advantages Disadvantages<br />
Implements a striped disk logical drive,<br />
the data is broken down into blocks and<br />
each block is written to a separate disk<br />
drive<br />
I/O performance is greatly improved by<br />
spreading the I/O load across many<br />
channels and drives<br />
No parity calculation overhead is<br />
involved<br />
Recommended Applications for RAID 1<br />
• Accounting<br />
• Payroll<br />
• Financial<br />
• Any application requiring very high availability<br />
Not a true RAID because it is not faulttolerant<br />
The failure of just one drive will result in<br />
all data in an logical drive being lost<br />
Should not be used in mission critical<br />
environments<br />
Advantages Disadvantages<br />
Simplest RAID storage subsystem<br />
design<br />
Can increase read performance by<br />
processing data requests in parallel<br />
since the same data resides on two<br />
different drives<br />
Very high disk overhead - uses only<br />
50% of total capacity