A virtual memory system has page size p and its corresponding file system has block size b and fixed-length record size r. Discuss the various relationships among p, b, and r that make sense. Explain why each of these possible relationships is reasonable.

Question

What will be an ideal response?

Answer 1

One possibility is that they are all the same; this would tend to trivialize the management
mechanisms, but it would likely not yield optimal performance.A better possibility is to
make the page size and the block size equivalent, and the block size a multiple of the fixedlength
record size. The block is the smallest unit of input/output transferred back and forth
between primary storage and secondary storage. It makes sense for the page to be of this size,
and perhaps the block size would be a small multiple of the page size. The spatial locality
phenomenon indicates that block paging several contiguous pages at a time would be an
effective anticipatory paging mechanism. Usually, blocks are considerably larger than the
amount of information stored in logical records, so it makes sense for the block size to be a
large multiple of the record size.