781. The working-set model implements the principle of

Operating System • Virtual Memory • UGC NET Paper 2 Computer Science JUNE 2013

782. RR scheduling of A,B,C,D,E bursts6,1,2,1,5 (1 ms slice) yields avg turnaround ________

Operating System • CPU Scheduling • UGC NET Paper 2 Computer Science JUNE 2013

783. With 10 resources and P,Q,R max8/7/5, alloc4/1/3, requests: P+2, Q+2, R+2. Safe request(s) are ________

Operating System • Deadlock Avoidance • UGC NET Paper 2 Computer Science JUNE 2013

784. Given I/O requests [65,80,110,100,175], head at 65 moving up at t=160, using SSTF and LOOK, seek times are:

Operating System • Disk scheduling • UGC NET Paper 2 Computer Science JUNE 2013

785. Unix with 12 direct, 1 indirect, 1 double-indirect pointers, block=256B, addr=2B. Max file size = ?

Operating System • File systems • UGC NET Paper 2 Computer Science JUNE 2013

786. Match: (a) Dangling ptr (b) Page fault (c) List repr (d) Toss-immediate — (i) Buffer-repl (ii) Variable-length records (iii) Object identifier (iv) Pointer swizzling

Operating System • Memory management • UGC NET Paper 2 Computer Science JUNE 2013

787. Portion of Windows 2000 that isn’t portable is ________

Operating System • OS Architecture • UGC NET Paper 2 Computer Science JUNE 2013

788. Match Windows OS layers: (a) HAL (b) Kernel (c) Executive (d) Win32 subsystem — (i)… (iv)…

Operating System • OS Architecture • UGC NET Paper 2 Computer Science JUNE 2013

789. 3-frame memory, ref string 5,4,3,2,1,4,3,5,4,3,4,1,4. FIFO and second-chance page faults are ________

Operating System • Page Replacement • UGC NET Paper 2 Computer Science JUNE 2013

790. Which is not true of distributed systems?

Operating System • Principles • UGC NET Paper 2 Computer Science JUNE 2013

791. Match process state transitions to reasons: Ready→Running; Blocked→Ready; Running→Blocked; Running→Ready vs dispatch, request satisfied, needs event, preemption.

Operating System • Process scheduling • UGC NET Paper 2 Computer Science JUNE 2013

792. Which Unix commands always display “WELCOME”?

Operating System • Shell scripting • UGC NET Paper 2 Computer Science JUNE 2013

793. Which is not true for UNIX OS?

Operating System • UNIX • UGC NET Paper 2 Computer Science JUNE 2013

794. Which is NOT required for critical-section solution?

Operating System • Concurrency • UGC NET Paper 2 Computer Science JUNE 2013

795. Two-level CPU scheduling is used because ___.

Operating System • CPU Scheduling • UGC NET Paper 2 Computer Science JUNE 2013

796. Debugger is a program that ___.

Operating System • Debugging Tools • UGC NET Paper 2 Computer Science JUNE 2013

797. A directory can be viewed as a ___ translating filenames to entries.

Operating System • File systems • UGC NET Paper 2 Computer Science JUNE 2013

798. Editor uses 200 K text (shared), 15 K stack, 50 K init data, 70 K bootstrap. Five instances need physical memory = ___.

Operating System • Memory Management • UGC NET Paper 2 Computer Science JUNE 2013

799. Paging: avg process size x, page size y, entry size z. Optimum page size minimizing overhead is ___.

Operating System • Memory Management • UGC NET Paper 2 Computer Science JUNE 2013

800. Demand paging: fault service=8 ms if no write, 20 ms if write (70% writes). Avg time = ___ ms?

Operating System • Memory Management • UGC NET Paper 2 Computer Science JUNE 2013