Compaq HSZ80 Network Card User Manual


 
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Compaq HSZ80 Array Controller ACS Version 8.3 Configuration and CLI Reference Guide
Using Stripesets to Increase I/O Performance
Stripesets enhance I/O performance by spreading the data across multiple disk drives.
Large I/O requests are broken into small segments called “chunks.” These chunks are
then “striped” across the disk drives in the storageset, thereby allowing several disk
drives to participate in one large I/O request or handle several I/O requests
simultaneously.
For example, in a three-member stripeset that contains disk drives 10000, 20000, and
30000, the first chunk of an I/O request is written to 10000, the second to 20000, the
third to 30000, the fourth to 10000, and so forth until all of the data has been written
to the drives.
Figure 3–3. Striping Lets Several Disk Drives Participate in Each I/O Request
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 let the controller set it automatically. See “Chunk Size,” page 3–51, for
information about setting the chunk size.
D
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CXO5507A
Chunk 1
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