I/O characteristics are used by the to determine the appropriate default and for a particular logical drive.
When you choose one of the logical drive I/O characteristics, the corresponding dynamic cache prefetch setting and segment size that are typically well suited for expected I/O patterns are populated in the Dynamic cache read prefetch field and the Segment size field.
You can change the cache read prefetch later by selecting Logical Drive >> Change >> Cache Settings . You can change the segment size later by selecting Logical Drive >> Change >> Segment Size .