每章作业.ppt

Chapter 1?1. What are the three main purposes of an operating system??2. What is the main advantage of multiprogramming??3. In a multiprogramming and time-sharing environment, several users share the system simultaneously. This situation can result in various security problems.?a. What are two such problems??b. Can we ensure the same degree of security in a time-shared machine as we have in a dedicated machine? Explain your -cont.?4. Define the essential properties of the following types of operating systems:?a. Batch?b. Interactive?c. Time sharing?d. Real time?e. Network?f. Distributed?5. Describe the differences between symmetric and asymmetric multiprocessing. What are three advantages and one disadvantage of multiprocessor systems??6. thinking: what kind of features may exist , IOT or CPS?Chapter 2?1. How does the distinction between monitor mode and user mode function as a rudimentary form of protection (security) system?? are the differences between a trap and an interrupt? What is the use of each function??3. Which of the following instructions should be privileged??a. Set value of timer.?b. Read the clock.?c. Clear memory.?d. Turn off interrupts.?e. Switch from user to monitor -cont.?4. Protecting the operating system is crucial to ensuring that puter system operates correctly. Provision of this protection is the reason behind dual-mode operation, memory protection, and the timer. To allow maximum flexibility, however, we would also like to place minimal constraints on the user. The following is a list of operations that are normally protected. What is the minimal set of instructions that must be protected??a. Change to user mode.?b. Change to monitor mode.?c. Read from monitor memory.?d. Write into monitor memory.?e. Fetch an instruction from monitor memory.?f. Turn on timer interrupt.?g. Turn off timer 3?1. What are the five major activities of an operating system in regard to process management??2. What are the three