Android Studio. Launch mode activity question. Thanks List all the launch mode o
ID: 3856361 • Letter: A
Question
Android Studio. Launch mode activity question. Thanks
List all the launch mode of activity. (b) Activity A uses the first mode (name end with letter "d"), Activity B uses the second mode (name end with letter "p"), Activity C uses the third mode (name end with letter "k"), Activity D uses the fourth mode (name end with letter "e"). If the activities are launched in the following order: A rightarrow A rightarrow C rightarrow C rightarrow B rightarrow C rightarrow B rightarrow B rightarrow D rightarrow A, ill the following stack table.Explanation / Answer
Under what circumstances do page faults occur? Describe the actions taken by the operating system when a page fault occurs. Answer: A page fault occurs when an access to a page that has not been brought into main memory takes place. The operating system verifies the memory access, aborting the program if it is invalid. If it is valid, a free frame is located and I/O is requested to read the needed page into the free frame. Upon completion of I/O, the process table and page table are updated and the instruction is restarted. 9.2 Assume that you have a page-reference string for a process with m frames (initially all empty). The page-reference string has length p; n distinct page numbers occur in it. Answer these questions for any page-replacement algorithms: a. What is a lower bound on the number of page faults? b. What is an upper bound on the number of page faults? Answer: a. n b. p 9.3 Consider the page table shown in Figure 9.30 for a system with 12-bit virtual and physical addresses and with 256-byte pages. The list of free page frames is D, E, F (that is, D is at the head of the list, E is second, and F is last). Convert the following virtual addresses to their equivalent physical addresses in hexadecimal. All numbers are given in hexadecimal. (A dash for a page frame indicates that the page is not in memory.) • 9EF • 111 29 30 Chapter 9 Virtual Memory • 700 • 0FF Answer: • 9E F - 0E F • 111 - 211 • 700 - D00 • 0F F - EFF 9.4 Consider the following page-replacement algorithms. Rank these algorithms on a five-point scale from “bad” to “perfect” according to their page-fault rate. Separate those algorithms that suffer from Belady’s anomaly from those that do not. a. LRU replacement b. FIFO replacement c. Optimal replacement d. Second-chance replacement Answer: Rank Algorithm Suffer from Belady’s anomaly 1 Optimal no 2 LRU no 3 Second-chance yes 4 FIFO yes 9.5 Discuss the hardware support required to support demand paging. Answer: For every memory-access op