Quiz submission record for quiz7-1-1 at Sun Aug  1 20:24:56 2004:

Your Answer for Question 1:
A Physical Address (PA) is an address that is used to directly reference the memory.  A Virtual Address (VA), however, is generated by the processor and can be translated to a PA through a combination of hardware and software.  VA's are mapped to PA's; it's possible for more than one VA to map to the same PA, which allows two different programs to share data or code.  VA's can also map to the disk.  To get a PA from a VA, we use the same page offset (lower bits), and pass the page number (upper bits) through some translation mechanism.

Your Answer for Question 2:
By having pages of fixed-sized chunks, we can keep some of the implementation of virtual memory invisible to the programmer and compiler.  If we use variable-sized chunks (segmentation), the address space is split into the segment number and offset, which the programmer and compiler must be aware of.  Bigger chunks are good for protection and for sharing in an address space.  Smaller chunks are good probably because they are faster and take up less space.


Your unique submission ID is quiz7-1-1-cs61c-ck-1091417096-459.