Segmentation
Consider a virtual memory architecture with the following parameters:- 44 bit virtual addresses
- virtual addresses that can address up to 16M segments
- 256 gigabytes (GB) of physical memory
- the segment tables are stored in physical memory (RAM)
- segment tables can start only on a 64 byte boundary
- segments can start only on a 64 byte boundary
- there are no permission or other extra bits.
Show how a virtual address gets mapped into a physical address. Be sure to show
- how the various fields of each address are interpreted;
- the size of each field (in bits);
- the maximum number of entries the Segment Table can hold; and
- the maximum size in bytes possible for the Segment Table;
- where any checks should be made for faults (invalid addresses).
Draw and label a diagram to answer this question.
The segment table has 224 (16M) entries, and an entry is 32+20 bits, which rounds up to 7 bytes. So the table has a maximum size of 7 × 224 bytes.