Virtual Memory

Question

The minimum number of page frames that must be allocated to a running process in a virtual memory environment is determined by

• Instruction Set Architecture
• page size
• physical memory size
• number of processes in memory

Why the answer for the above question is “ISA” ??

Please explain the concept behind it 

 

Answer 1

Yes, ISA decides the minimum no.of frames that must be allocated for a process.

For a process that contain instructions which contain 1 memory operand, we need atleast two frames 1 for instruction, 1 for operand.Suppose the same Instruction, if it uses indirect addressing mode, then we will need another frame because of the Indirection.So we need a total of 3 frames.Like wise , the no.of frames that must be allocated to a process may increase with the indirection.

Thus Instruction Set Architecture plays a crucial role in deciding what are the minimum frames that must be allocated for a process.