Important Questions of Operating System Introduction to OS Q1: What is distributed system? Q2: what are the various functions of OS? Q3: name any four multi- user OS? Q4: What is main goal of memory management? Q5: What is Real time OS (RTS)? Q6: What is spooling? **Q7: Difference b/t Multiprogramming and multitasking. **Q8: What is OS? Discuss its classification. Q9: List the function of OS? Q10: What is multiprogramming? What are the factors effecting the degree of multiprogramming. OS architecture Q1: What is system call? Q2: What is spooling? Q3: What is garbage collection? Processes and threads Q1: Explain the difference between the process and a program? Q2: Difference between the process and thread? **Q3: What do you mean by PCB? Q4: List some reason for process termination. Q5: What are the reasons for the process suspension? CPU Scheduling **Q1: Define preemptive and non preemptive scheduling. [dec 10] **Q2: What is a scheduler? How many types of schedulers coexist in a complex OS? Explain [m 09] Q3: List various scheduling algorithm. [dec 09] Q4: Explain by taking example of RR scheduling algorithm. Q5: Discuss different factors which are taken in to account while selecting a CPU scheduling algorithm. IPC and synchronization ***Q1: Define critical section. How it can be managed. [dec2008,2009] Q2: What is busy waiting? [dec 2006,may2006] **Q3: What are semaphores? [may 2008] Q4: Write note on Synchronization. [dec 2006,may 2008] Q5: Discuss concurrency? (^th edition page 229) Q6: Differentiate between program and process. Deadlock Q1: Whatis deadlock? List and explain four necessary conditions for dead lock to occur? Explain different algorithms for prevention and avoidance of deadlocks. [Dec 2009, May 2006, Dec 2006] (List the various strategies to deal with deadlock) Q2: What is resource allocation graph? [Dec 2008] 1 AmAn Q3: List the Coffman's conditions that leads to a Deadlock. [Dec 2006] Q4: Explain the technique for Deadlock avoidance. //Bankers Algo Q5: When is a system in safe state? [Dec 2008, May 2006] Q6: How can you prevent circular waiting situation in Deadlock? [May 2008] Memory Management Q1: What is logical address space? [May 2008] Q2: What is physical address? Q3: Explain Swapping and its advantage? [Dec 2006, Dec 2007] **Q4: Explain the difference between internal and external fragmentation? Q5: Define Compaction. [Dec 2008] **Q6: Why are page sizes always power of 2? [Dec 2008] Q7: Explain the algorithm: (a) First Fit, (b) Worst Fit & (c ) Best Fit. [may 2007,2009] Q8: Explain about paging? [Dec 2006] Q9: Explain the concept of segmentation taking suitable example? [dec 2009] Q10: What are the various memory management techniques? Discuss with example. Q11: List various free space management techniques and explain them. Virtual memory Q1: What is virtual memory? Explain the advantages of it? Q2: What are the logical page replacement and global page replacement? Q3: Describe the Belady's anomaly. Explain with example? **Q4: What is thrashing? How does the system detect thrashing? What can the system do to eliminate the problem? ***Q5: What so you mean by page faults? When do page fault occur? Describe the action taken by OS when page fault occurs? ((((( Solve: Consider a main memory with capacity of 4 page frames. Assume that the pages of a process are referenced in the order as given below: 1, 3, 4, 4, 3, 2, 1, 7, 5, 6, 4, 2, 1, 2))))) Q6: Explain virtual memory and associative memory. Q7: A variable partition memory system has at some point in time the following hole sizes in the given order :- 20k, 15k, 40k, 60k, 10k, 25k. A New process is to be loaded. Which hole size would be filled using best-fit, first-fit and worst-fit respectively File- System Interface/ File-System Implementation **Q1: What is file system? Explain file protection and allocation methods. Q2: What do you mean by file management? Explain the various access and allocation methods of files in detail. I/O Systems 2 AmAn Mass-Storage Structure Q1: Suppose that the head of moving head-disk with 200 tracks, numbered 0 to 199, has just finished a request at track I25. The queue of the requests is kept in FIFO order : 86, 147,91, 177,94, I50, 102, 175, 130. What is the total number of head movements needed to satisfy requests for the following disk Scheduling algorithms :(a) FCFS (b) SSTF (c) Scan. Distributed Structures/ Distributed File System / Distributed Coordination Q1: What is a distributed system? Q2: What are distributed and non distributed operating systems? Q3: Compare and contrast Public - key cryptography technique with conventional cryptography technique. Q4: Discuss multiprocessor and distributed operating systems with their merits and demerit. Protection/Security Q1: Differentiate between protection and security. (1mark). Q2: Discuss in detail Data Encryption Standard (DES) algorithm. What are its disadvantages? Q3: Compare and contrast Public-key cryptography technique with Conventional cryptography technique. Q4: Differentiate between virus and Trojan horse. Case Studies (LINUX) Q1: What is Process in Linux? Explain '&' and 'kill' in detail. **Q2: Explain the architecture of LINUX Operating System. Q3: Explain how UNIX has a better policy to handle smaller files than the larger files? Explain how UNIX is booted. Show inode structure in UNIX. Miscellaneous Q1: What is reentrant code? What is better to share a reentrant code out of paging and segmentation? Q2: Give an example of producer-consumer problem, indicating the reasons for inconsistency that can arise due to race conditions. “May good luck be your friend in whatever you do and may trouble be always a stranger to you.” ~Irish Blessings quotes 3 AmAn