Which cache algorithm will optimize a storage array’s I/O response time if sequential access is
detected?

A.
Flushing

B.
Least recently used

C.
Read ahead

D.
Write-through

Explanation:

Read Operation with Cache
A prefetch or read-ahead algorithm is used when read requests are sequential. In a sequential
read request, a contiguous set of associated blocks is retrieved. Several other blocks that have not
yet been requested by the host can be read from the disk and placed into cache in advance. When
the host subsequently requests these blocks, the read operations will be read hits. This process
significantly improves the response time experienced by the host. The intelligent storage system
offers fixed and variable prefetch sizes. In fixed prefetch, the intelligent storage system prefetches
a fixed amount of data. It is most suitable when host I/O sizes are uniform. In variable prefetch, the
storage system prefetches an amount of data in multiples of the size of the host request.
Maximum prefetch limits the number of data blocks that can be prefetched to prevent the disks

from being rendered busy with prefetch at the expense of other I/Os.