Operating System

1) What is the general role of an operating system?
Provide a set of services to system users
2) What are the four main structural elements of a computer?
Processor, Main Memory, I/O Modules, System Bus
3) What are the two basic types of registers?
User visible and control/status registers
4) Address registers may contain:
Memory addresses of instructions, Memory addresses of data, Partial Memory Addresses
5) What are the two basic steps used by the processor in instruction processing?
Fetch and execute
6) A primary object of an operating system is:
Convenience, Efficiency, Ability to evolve
7) The operating system provides many types of services to end-users, system programmers, and system designers, including:
Error detection and response
8) The operating system is unique in its role as a control mechanism, in that:
It frequently relinquishes control of the system processor and must rely on the processor to regain control of the system
9) Operating systems must evolve over time because:
New hardware is designed and implemented in the computer system
10) A major problem with early serial processing systems was:
Setup time*, Scheduling
11) Relative to information protection and security in computer systems, access control typically refers to:
Regulating user and process access to the data aspect of the system
12) The paging system in memory management system provides for mapping between the virtual address and:
Real address
13) Which of the following major lines of computer system development created problems in timing and synchronization that contributed to the development of the concept of the process?
Multiprogramming batch operation systems, Time sharing systems, Real time transaction systems
14) The principle object of a time sharing system, multiprogramming system is to:
None of the above (NOT maximize processor use, maximize response time, or provide exclusive access to hardware) (FAIRNESS)
15) A computer hardware feature that is vital to the effective operation of a multiprogramming operating system is:
I/O interrupts and DMA
16) The behavior of a processor can be characterized by examining:
The interleaving of the process traces
17) The basic Two-State Process Model defines two possible states for a process in relationship to the processor:
Running and Not Running
18) There are a number of conditions that can lead to process termination, including:
Parent termination, Bounds violation, Normal completion
19) In the Five-State Process Model, the following represents a valid state transition:
Running -> Blocked
20) The scheduling strategy where each process in the queue is given a certain amount of time, in turn, to execute and then returned to the queue, unless blocked is referred to as:
Round-Robin
21) Which of the following is true, regardless of the relationship between processes and threads:
It takes far less time to create a new thread in an existing process than to create a new process
22) The basic thread operation related to the change in thread state that occurs when a thread needs to wait for an event is referred to as the:
Block operation
23) One of the disadvantages of user-level threads (ULT) compared to kernel level threads (KLT) is:
When a ULT executes a system call, all threads in the process are blocked
24) In the Linux O/S, multiple threads may be created and executed within a single process. This is an example of the following Thread-to-Process relationship:
M:1
25) In a SMP system, each processor maintains a local cache and must alert all other processers that a change to cache update has taken place. This is referred to as the:
Cache coherency problem
1) The permanent blocking of a set of processes that either compete for system resources or communicate with each other is called:
Deadlock
2) All deadlocks involve conflicting needs for resources by:
Two or more processes
3) A resource that can be created and destroyed is called a:
Consumable Resource
4) A condition of policy that must be present for a deadlock to be possible is:
Mutual Exclusion, No Preemption, Hold and Wait
5) A direct method of deadlock prevention is to prevent the occurrence of:
Circular Wait
6) In the Resource Allocation Denial approach to Deadlock Avoidance, a safe state is defined as one in which:
At least one potential process sequence does not result in deadlock
7) A conservative strategy for dealing with deadlocks that involves limiting access to resources and imposing restrictions on processes is called:
Deadlock Prevention
8) In deadlocked process recovery, selection criteria for choosing a particular process to abort or rollback including designating the process with the:
Least total resources allocated so far, Lowest Priority, Most estimated time remaining
9) The Dining Philosopher’s Problem is a standard test case for evaluating approaches to implementing:
Synchronization
10) A liberal strategy for dealing with deadlocks that involves limiting access to resources and imposing restrictions on processes is called:
Deadlock Detection
11) The concept of memory management satisfies certain requirements including:
Protection, Physical Organization, Relocation
12) The concept of virtual memory is based on one or both of two basic techniques:
Segmentation and paging
13) A problem with the largely obsolete Fixed Partitioning memory management technique is that of:
Allowing only a fixed number of processes, Internal fragmentation, Inefficient use of memory
14) The problem of internal fragmentation can be lessened in systems employing a fixed-partition memory management scheme, by using:
Unequal size partitions
15) In the Dynamic Partitioning technique of memory management, the placement algorithm that chooses the block that is closest in size to the request is called:
Best-fit
16) In a system employing a segmentation scheme for memory management, a process is divided into:
A number of segments which need not be of equal size
17) In a system employing a segmentation scheme for memory management, wasted space is due to:
External fragmentation
18) In a system employing a paging scheme for memory management, wasted space is due to:
Internal fragmentation
19) The page table for each process maintains:
The frame location for each page of a process
20) An actual location in main memory is called a(n):
Absolute address
21) The type of memory that allows for very effective multiprogramming and relieves the user of memory size constraints is referred to as:
Virtual memory
22) The situation where the process spends most of its time swapping process pieces rather than executing instructions is called:
Thrashing
23) The situation that occurs when the desired page table is not found in the Translation Lookaside Buffer (TLB) is called a:
TLB miss
24) The real address of a word in memory is translated from the following portions of a virtual address:
Page number and offset
25) Segmentation has a number of advantages to the programmer over a non-segmented address space, including:
Sharing among processes, Simplifying the handling of growing data structures, Protection
26) The concept associated with determining the number of processes that will be resident in main memory is referred to as:
Load control
27) The replacement policy that is impossible to implement because it would require the O/S to have perfect knowledge of future events is called the:
Optimal policy
28) The fetch policy that exploits the characteristics of most secondary memory devices, such as disks, which have seek time and rotational latency is called:
Prepaging
29) A fundamental choice in the design of the memory management portion of an O/S is:
Whether to use paging, segmentation, or a combination of the two, The algorithms employed for various aspects of memory management, Whether or not to use virtual memory techniques
30) In a combined paging/segmentation system, a user’s address space is broken up into a number of:
Segments or pages, at the discretion of the programmer