Operating System Assignment 1
I have a delivery deadline in 6 days and it is worth 10 points on average. I want a correct solution if possible. Thank you. If possible, please provide the solution in the same image or in Word.
1. What is meant by Direct Memory Access (DMA)?
In virtually all systems that include DMA modules, DMA access to main memory is given higher priority than processor access to main memory. Why?
2. Suppose the hypothetical processor in the given figure has two I/O instructions:
1.0011 Load AC from I/O
2.0111 Store AC to I/O
0
3
4
15
In these cases, the 12-bit address identifies a particular external device.
Opcode
(a) Instruction format
Show the program execution for the following program:
15
Magnitude (b) Integer format
1. Load AC from device 5
2. Add contents of memory location 940.
3. Store AC to device 6
Program counter (PC) = Address of instruction
Instruction register (IR) = Instruction being executed
Accumulator (AC) = Temporary storage
(c) Internal CPU registers
Assume that:
- The next value retrieved from device 5 is 3
- The location 940 contains a value of 2
3. What is Virtual Memory? Briefly explain how the system implements the concept of virtual memory. Also explain Virtual Address and Real Address.
4. What is Cache Memory? What are the different levels of Cache Memory? Differentiate Cache and Main Memory Cache and Virtual Memory.
5. State whether each of the following is true or false; if false, explain:
a) Uniprogramming typically provides better utilization of system resources than multiprogramming.
b) Cache memory enables the processor to access data more quickly than it can access regular RAM.
c) Modern Unix OS such as Linux has been built based on Microkernel.
d) The operating system maintains information that can be used for billing purposes on multi-user systems.