HSG80 Array Controller ACS Version 8.2 User Guide (EK-HSG80-UG. B01, July 1998)

Creating Storagesets 3–49
Increasing the Data Transfer Rate
A small chunk size relative to the average request size increases the
data transfer rate by allowing multiple disk drives to participate in one
I/O request. This concept is shown in Figure 3–19.
Figure 3–19 Chunk Size Smaller than the Request Size
Applications such as CAD, image processing, data collection and
reduction, and sequential file processing tend to require high data-
transfer rates.
Increasing Sequential Write Performance
For stripesets (or striped mirrorsets), use a large chunk size relative to
the I/O size to increase the sequential write performance. A chunk size
of 256 generally works well.
Chunk size does not significantly affect sequential read performance.
CXO-5172A-MC
Chunk size = 128k (256 blocks)
A
1
A
4
A
2
A
3
Request A