M. Tech. in Computer Engineering Advanced Operating System First Test Examination
February 1, 2009
Note First Question is Compulsory. Answer any four questions from (2) to (6) 1. Objective Questions (a) Which One of the following is not the drawback of Kernel-based approach of Operating System Design i. ii. iii. iv. The Kernel size Protection of user and kernel address space Lack of Extensibility Bad Maintainability
(b) Adding a new functionality to kernel-based OS needs / does not need recompilation of the OS kernel. (Choose Appropriate word) (c) In micro-Kernel- based OS, Inter-process communication mechanisms are implemented as i. ii. iii. iv. Micro-processor Instructions System Calls User Defined Function Hardware Interrupts
(d) Which one of the following doesn’t lead to saving of process context i. Termination of process ii. Creation of Process iii. A process returning from execution of open() to execute a user defined function iv. A process returning from interrupt handling to user mode (e) A process is executing user defined function called HellowW orld(), the level of kernel stack and user stack will be i. zero, zero 1
ii. nonzero, zero iii. zero, nonzero iv. nonzero,nonzero 2. Design an algorithm that translate virtual address to physical address, given the virtual address and the address of the pregion entry. 3. It is possible to implement the system such that the kernel stack grows on top of the user stack. discuss the advantages and disadvantages of such an implementation. 4. In a micro-kernel based OS, concepts such as (i)Address Spaces, (ii) Threads and IPC, and (iii) Unique Identifiers are implemented as core concepts. Will this design lead to a flexible operating system ? If yes, what are the additional components found in monolithic OS can be implemented on top of it? and How? 5. Draw and explain state transition diagram for depicting life cycle of UNIX process 6. Compare and Contrast monolithic and micro kernel approach of OS design using following features (a) Inter Process Communication (b) Memory Management (c) Security and Stability (d) IO communication (e) Extensibility and Portability
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