Please answer these question correctly True or False and briefly explain if fals
ID: 3584854 • Letter: P
Question
Please answer these question correctly
True or False and briefly explain if false
a) Multiprogramming is responsible to allow CPU to switch jobs so frequently that users can interact with each job while it is running (thus interactive computing).
b) In the dual-mode operation of an OS, the mode bit can be set by software or user.
2. Please fill each of the following conditions (a-f) into its appropriate state transition. Note: some transitions may not happen at all.
a. admitted
b. exit
c. interrupt
d. I/O or event completion
e. I/O or event wait
f. scheduler dispatch
new -----------------> ready
ready -----------------> waiting
waiting -----------------> running
ready -----------------> running
running -----------------> waiting
running -----------------> ready
running -----------------> terminated
waiting -----------------> ready
3. Briefly answer the following questions
a) Explain the relation of bootstrap program (sometimes called firmware) and kernel.
b) Why do some I/O devices have local buffers? How is this buffer used in the interaction between the I/O device and the CPU?
c) What is the condition for a process to be moved from ready queue to I/O queue? What is the condition for a process to be moved from I/O queue to ready queue?
d) Explain the critical section problem.
Explanation / Answer
Please follow the data and description :
1)
a) Multiprogramming is responsible to allow CPU to switch jobs so frequently that users can interact with each job while it is running (thus interactive computing). - TRUE.
b) In the dual-mode operation of an OS, the mode bit can be set by software or user. - FALSE
Reason: In the computer system there are mainly two separate modes of operation called as "user mode" and "monitor mode". A bit, called the "mode bit", is added to the hardware of the computer to indicate the current mode wheter is it in a monitor (0) or user (1). With the mode bit, the users are able to distinguish between an execution that is done on behalf of the operating system, and one that is done on behalf of the user. At inital system boot time, the hardware starts in monitor mode. The operating system is then loaded, and starts user processes in user mode. Whenever a trap or interrupt occurs, the hardware switches from user mode to monitor mode which means that it changes the state of the mode bit to be 0. Thus, whenever the operating system gains control of the computer, it is in monitor mode. The system always switches to user mode, by setting the mode bit to 1 before passing control to a user program.
2)
a. admitted - This transitions may not happen at all.
b. exit - It corresponds to the transition of "running -------> terminated".
c. interrupt - It corresponds to the transition of "running -------> waiting".
d. I/O or event completion - It corresponds to the transition of "waiting -------> ready".
e. I/O or event wait - It corresponds to the transition of "ready -------> waiting".
f. scheduler dispatch - It corresponds to the transition of " ready -------> running".
Hope this is helpful.