os
Multiple Choice Questions 1
Question1 The general role of an operating system is to:
选择一个答案
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a. Provide a set of services to system users |
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b. Manage files for application programs |
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c. Act as an interface between various computers |
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d. None of the above |
Feedback:
A. 为系统用户提供一系列服务
B. 为应用程序管理文件(这显然不是)
C. 作为多台计算机间的接口(应该是CPU与硬件之间的接口)
D. error
Question2
Information that must be saved prior to the processor transferring control to the interrupt handler routine includes:
选择一个答案
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a. Program Status Word (PSW) & Contents of processor registers |
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b. Program Status Word (PSW) |
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c. None of the above |
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d. Program Status Word (PSW) & Location of next instruction |
Feedback:
D.程序状态字和下个指令的位置 P14
Question3
One accepted method of dealing with multiple interrupts is to:
选择一个答案
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a. Service them in round-robin fashion |
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b. Disable all interrupts except those of highest priority |
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c. None of the above |
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d. Define priorities for the interrupts |
Feedback:
处理多个中断的方法 P18
The first is to disable interrupts while an interrupt is being processed.
A second approach is to define priorities for interrupts and to allow an interrupt of higher priority to cause a lower-priority interrupt handler to be interrupted.
A. 轮循服务(显然错误)
B. 只服务优先级高的，忽视优先级低的
C. error
D. 为这些中断定义优先级
Question4
In a uniprocessor system(单处理器系统), multiprogramming(多道程序设计) increases processor efficiency by:
选择一个答案
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a. Taking advantage of time wasted by long wait interrupt handling |
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b. Eliminating all idle processor cycles |
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c. All of the above |
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d. Increasing processor speed |
Feedback:
A.利用等待中断的时间 P18
Question5
As one proceeds down the memory hierarchy (i.e., from inboard memory to offline storage), the following condition(s) apply:
选择一个答案
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a. Decreasing capacity |
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b. Increasing access time |
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c. All of the above |
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d. Increasing cost per bit |
Feedback:
A.容量 ↑
B.访问时间 ↑
C.error
D.价格 ↓
Question6
Small, fast memory located between the processor and main memory is called
选择一个答案
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a. WORM memory |
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b. CD-RW memory |
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c. None of the above |
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d. Cache memory |
Feedback:
D.存储器的层次结构由上至下依次为：寄存器(processer)，高速缓存，主存储器(memory)，磁盘，磁带
Question7
When a new block of data is written into cache memory, the following determines which cache location the block will occupy:
选择一个答案
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a. None of the above |
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b. Cache size |
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c. Block size |
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d. Write policy |
Feedback:
Nothing will change.
高速缓冲存储器设计：cache size，block size,mapping function,replacement algorithm,write policy.
Question8
The four main structural elements of a computer system are:
选择一个答案
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a. None of the above |
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b. Processor, Registers, Main Memory & System Bus |
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c. Processor, Main Memory, I/O Modules & System Bus |
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d. Processor, Registers, I/O Modules & Main Memory |
Feedback:
计算机有四个主要的结构化部件：处理器、主存储器、输入/输出模块、系统总线 P6
Question9
The two basic types of processor registers are:
选择一个答案
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a. User-visible and Control/Status registers |
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b. Control and Status registers |
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c. User-visible and user-invisible registers |
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d. None of the above |
Feedback:
用户可见寄存器：数据寄存器、地址寄存器、索引寄存器、段指针、栈指针
控制和状态寄存器：程序计数器PC、指令寄存器IR
Question10
Address registers may contain
选择一个答案
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a. Partial memory addresses |
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b. Memory addresses of data |
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c. Memory addresses of instructions |
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d. All of the above |
Feedback:
A.辅存地址
B.数据的主存储器地址
C.指令的主存储器地址
Question11
A Control/Status register that contains the address of the next instruction to be fetched is called the:
选择一个答案
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a. Program Counter (PC) |
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b. All of the above |
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c. Instruction Register (IR) |
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d. Program Status Word (PSW) |
Feedback:
A. Program counter (PC) = Address of instruction
C. Instruction register (IR) = Instruction being executed
D. Program Status Word (PSW) = contains status information
Question12
The two basic steps used by the processor in instruction processing are:
选择一个答案
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a. None of the above |
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b. Fetch and Instruction cycles |
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c. Fetch and Execute cycles |
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d. Instruction and Execute cycles |
Feedback:
In its simplest form, instruction processing consists of two steps: The processor reads (fetches) instructions from memory one at a time and executes each instruction. P9
Question13
A fetched instruction is normally loaded into the:
选择一个答案
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a. Accumulator (AC) |
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b. None of the above |
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c. Instruction Register (IR) |
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d. Program Counter (PC) |
Feedback:
Instruction register (IR) = Instruction being executed
A. Accumulator (AC) = Temporary storage 临时存储体
Question14
A common class of interrupts is
选择一个答案
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a. Program |
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b. I/O |
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c. Timer |
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d. All of the above |
Feedback:
Classes of interrupts:
Program, Timer, I/O, Hardware failure
Question15
When an external device becomes ready to be serviced by the processor, the device sends this type of signal to the processor:
选择一个答案
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a. Handler signal |
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b. None of the above |
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c. Interrupt signal |
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d. Halt signal |
Feedback:
请求中断信号
Multiple Choice Questions 2
Question1
A primary objective of an operating system is:
选择一个答案
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a. Ability to evolve |
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b. Convenience |
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c. Efficiency |
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d. All of the above |
Feedback:
操作系统的三个主要目标：方便，有效，扩展的能力
Question2
The paging system in a memory management system provides for dynamic mapping between a virtual address used in a program and:
选择一个答案
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a. A real address in a program |
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b. None of the above |
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c. A virtual address in main memory |
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d. A real address in main memory |
Feedback：
The paging system provides for a dynamic mapping between the virtual address used in the program and a real address, or physical address, in main
memory. P51
Question3
Relative to information protection and security in computer systems, access control typically refers to:
选择一个答案
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a. The flow of data within the system |
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b. Proving that security mechanisms perform according to specification |
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c. Regulating user and process access to various aspects of the system |
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d. None of the above |
Feedback：
调节用户和进程对系统方方面面的访问权限
Question4
A common problem with full-featured operating systems, due to their size and difficulty of the tasks they address, is:
选择一个答案
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a. Sub-par performance |
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b. Chronically late in delivery |
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c. All of the above |
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d. Latent bugs that show up in the field |
Feedback：
一个功能完善的操作系统的大小和它所处理任务的困难性，导致了四个让人遗憾但又普遍存在的问题：
① 操作系统在交付使用时习惯性表现出落后
② 系统有潜在的错误
③ 总是难以达到期望的性能
④ 不可能开发出既复杂又不易受各种安全性攻击的操作系统
P 54
Question5
A technique in which a process, executing an application, is divided into threads that can run concurrently is called:
选择一个答案
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a. None of the above |
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b. Multithreading |
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c. Symmetric multiprocessing (SMP) |
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d. Multiprocessing |
Feedback：
Multithreading is a technique in which a process, executing an application, is divided into threads that can run concurrently. P56
Question6
WIN2K supports several types of user applications, including:
选择一个答案
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a. Linux |
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b. System 10 |
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c. WIN32 |
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d. None of the above |
Feedback：
Nothing~
Question7
Key to the success of Linux has been it’s character as a free software package available under the auspices of the:
选择一个答案
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a. Berkeley Software Distribution |
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b. Free Software Foundation |
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c. World Wide Web Consortium |
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d. None of the above |
Feedback：
Key to the success of Linux has been the availability of free software packages
under the auspices of the Free Software Foundation (FSF). P70
Question8
The operating system provides many types of services to end-users, programmers and system designers, including:
选择一个答案
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a. Built-in user applications |
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b. All of the above |
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c. Relational database capabilities with the internal file system |
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d. Error detection and response |
Feedback：
the OS typically provides services in the following areas：• Program development • Program execution • Access to I/O devices
• Controlled access to files • System access • Error detection and response • Accounting
Question9
The operating system is unusual in it’s role as a control mechanism, in that:
选择一个答案
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a. It runs on a special processor, completely separated from the rest of the system |
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b. It never relinquishes control of the system processor |
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c. None of the above |
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d. It frequently relinquishes control of the system processor and must depend on the processor to regain control of the system |
Feedback：
• The OS functions in the same way as ordinary computer software; that is, it is a program or suite of programs executed by the processor.
• The OS frequently relinquishes control and must depend on the processor to allow it to regain control. P40
Question10
Operating systems must evolve over time because
选择一个答案
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a. Users will only purchase software that has a current copyright date |
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b. New hardware is designed and implemented in the computer system |
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c. All of the above |
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d. Hardware must be replaced when it fails |
Feedback：
计算机需要不断发展的原因：硬件升级和新型硬件的出现、新的服务、纠正错误
P 40/41
Question11
A major problem with early serial processing systems was:
选择一个答案
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a. Inability to get hardcopy output |
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b. Setup time |
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c. Lack of input devices |
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d. All of the above |
Feedback：
调度和准备时间
Question12
An example of a hardware feature that is desirable in a batch-processing system is
选择一个答案
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a. None of the above |
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b. A completely accessible memory area |
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c. Large clock cycles |
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d. Privileged instructions |
Feedback：
内存保护、定时器、特权指令、中断
Question13
A computer hardware feature that is vital to the effective operation of a multiprogramming operating system is:
选择一个答案
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a. Very large memory |
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b. Multiple processors |
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c. I/O interrupts and DMA |
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d. All of the above |
Feedback：
支持I/O中断和直接存储器访问
Question14
The principle objective of a time sharing, multiprogramming system is to
选择一个答案
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a. Maximize processor use |
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b. None of the above |
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c. Provide exclusive access to hardware |
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d. Maximize response time |
Feedback：
批处理多道程序设计是为了充分使用处理器，分时多道程序设计是为了减小响应时间
Question15
Which of the following major line of computer system development created problems in timing and synchronization that contributed to the development of the concept of the process?
选择一个答案
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a. Multiprogramming batch operation systems |
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b. Real time transaction systems |
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c. All of the above |
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d. Time sharing systems |
Feedback：
Three 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, time sharing, and real-time transaction systems.
Question16
Which of the following major line of computer system development created problems in timing and synchronization that contributed to the development of the concept of the process?
选择一个答案
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a. Multiprogramming batch operation systems |
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b. Real time transaction systems |
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c. Time sharing systems |
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d. All of the above |
Multiple Choice Questions 3
Question1
The behavior of a processor can be characterized by examining:
选择一个答案
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a. Multiple process traces |
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b. A single process trace |
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c. All of the above |
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d. The interleaving of the process traces |
Feedback:
We can characterize behavior of the processor by showing how the traces of the various processes are interleaved. P81
Question2
The Process Image element that contains the modifiable part of the user space is called the:
选择一个答案
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a. User Program |
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b. None of the above |
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c. System Stack |
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d. Process Control Block |
Feedback:
User data.
Question3
The processor execution mode that user programs typically execute in is referred to as:
选择一个答案
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a. System mode |
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b. None of the above |
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c. User mode |
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d. Kernel mode |
Feedback:
用户态。System mode = kernel mode
Question4
One step in the procedure for creating a new process involves:
选择一个答案
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a. Assigning a unique identifier |
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b. All of the above |
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c. Allocating space for the process |
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d. Initializing the process control block |
Feedback：
P99 12345
Question5
A process switch may occur when the system encounters an interrupt condition, such as that generated by a:
选择一个答案
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a. All of the above |
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b. Trap |
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c. Supervisor call |
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d. Memory fault |
Feedback：
中断：时钟中断、I/O中断、内存失效
陷阱
系统调用
Question6
In the Process Based O/S:
选择一个答案
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a. None of the above |
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b. Major kernel functions are organized as separate functions |
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c. The User Process Image includes a kernel stack |
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d. O/S code and data are contained in the shared address space |
Feedback：
主要的内核函数被组织成独立的进程 P103
Question7
In a typical UNIX system, the element of the process image that contains the processor status information is the:
选择一个答案
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a. All of the above |
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b. System-level context |
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c. Register context |
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d. User-level context |
Feedback：
处理器状态信息保存在寄存器上下文中
Question8
The behavior of an individual process can be characterized by examining:
选择一个答案
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a. The interleaving of the process traces |
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b. All of the above |
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c. Multiple process traces |
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d. A single process trace |
Feedback:
独立的进程：单独的进程轨迹
Question9
The basic Two-State Process Model defines two possible states for a process in relationship to the processor:
选择一个答案
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a. Running and Executing |
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b. Running and Not Running |
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c. None of the above |
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d. Executing and Waiting |
Feedback:
运行和非运行两种状态
Question10
There are a number of conditions that can lead to process termination, including:
选择一个答案
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a. Normal completion |
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b. Parent termination |
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c. All of the above |
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d. Bounds violation |
Feedback：
P 85
Question11
In the Five-State Process Model, the following represents a valid state transition:
选择一个答案
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a. All of the above |
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b. New -> Blocked |
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c. New -> Running |
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d. Running -> Blocked |
Feedback：
Null -> New / New -> Ready / Ready -> Running / Running -> Exit / Running -> Ready / Running -> Blocked / Blocked -> Ready / Ready -> Exit / Blocked -> Exit
Question12
In a Process Model that implements two suspend states, a valid state transition is represented by:
选择一个答案
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a. Ready -> Ready/Suspend |
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b. Running -> Ready/Suspend |
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c. Ready/Suspend -> Ready |
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d. All of the above |
Feedback:
P 89/90
Question13
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:
选择一个答案
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a. Round-Robin |
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b. Prioritization |
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c. All of the above |
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d. LIFO |
Feedback:
Round-Robin 轮循 P84
Question14
A Memory Table is an O/S control structure that is used by the O/S to:
选择一个答案
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a. Manage I/O devices |
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b. Provide information about system files |
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c. None of the above |
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d. Manage processes |
Feedback：
Memory tables are used to keep track of both main (real) and secondary
(virtual) memory.
Question15
The Process Image element that contains the collection of attributes needed by the O/S to control a particular process is called the:
选择一个答案
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a. User Data |
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b. System Stack |
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c. None of the above |
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d. Process Control Block |
Feedback：
进程控制块
Multiple Choice Questions 4
Question1
The concept of a process in an operating system embodies two primary characteristics, one of which is:
选择一个答案
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a. None of the above |
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b. Resource ownership |
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c. Symmetric multiprocessing |
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d. Multithreading |
Feedback:
资源所有权、调度/执行
Question2
Early operating systems that were designed with little concern about structure are typically referred to as:
选择一个答案
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a. Monolithic operating systems |
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b. Kernel operating systems |
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c. All of the above |
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d. Layered operating systems |
Feedback：
单体结构的操作系统
Question3
A benefit of the microkernel organization is:
选择一个答案
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a. Flexibility |
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b. All of the above |
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c. Portability |
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d. Extensibility |
Feedback：
一致接口、可扩展性、灵活性、可移植性、可靠性、分布式系统支持、对面向对象操作系统的支持
Question4
In low-level microkernel memory management, an example of an operation that can support external paging and virtual memory management is the:
选择一个答案
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a. Map operation |
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b. Flush operation |
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c. Grant operation |
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d. All of the above |
Feedback：
三个微内核操作支持内核外的分页和虚存管理
授权、映射、刷新 P129
Question5
In a W2K system, the state that a thread enters when it has been unblocked and the resource for which it has been blocked is not yet available is called the:
选择一个答案
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a. Waiting state |
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b. Standby state |
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c. None of the above |
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d. Transition state |
Feedback：
过渡态
Question6
In a Solaris system, a User-Level Thread (ULT) that enters the active state is assigned to a:
选择一个答案
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a. Heavy-Weight Process (HWP) |
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b. Light-Weight Process (LWP) |
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c. None of the above |
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d. Kernel thread |
Feedback：
轻量级进程
Question7
In a Linux system, when a new process is cloned, the two processes share the same:
选择一个答案
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a. Process identifier |
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b. Virtual memory |
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c. task_struct data structure |
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d. All of the above |
Feedback：
克隆后共享同一个虚存
Question8
An example of a system that implements a single process with multiple threads is:
选择一个答案
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a. WIN 2000 |
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b. All of the above |
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c. Solaris |
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d. Java |
Feedback：
P 113
Question9
Which of the following is true regarding the relationship between processes and threads:
选择一个答案
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a. It takes less time to switch between two different processes than to switch between two threads within the same process |
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b. It takes far less time to create a new thread in an existing process than to create a new process |
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c. It takes less time to terminate a process than a thread |
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d. All of the above |
Feedback：
Nothing~
Question10
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:
选择一个答案
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a. Unblock operation |
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b. None of the above |
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c. Spawn operation 派生 |
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d. Block operation |
Feedback：
显然阻塞
Question11
One of the disadvantages of User-Level Threads (ULTs) compared to Kernel-Level Threads (KLTs) is:
选择一个答案
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a. All of the above |
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b. When a ULT executes a system call, all threads in the process are blocked |
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c. Scheduling is application specific |
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d. Thread switching does not require kernel mode privileges |
Feedback：
P 119/120
Question12
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:
选择一个答案
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a. 1:M |
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b. 1:1 |
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c. None of the above |
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d. M:N |
Feedback：
Thread ：Process = M ：1
Question13
The computer system category where a single processor executes a single instruction stream to operate on data stored in a single memory is called:
选择一个答案
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a. Single Instruction Multiple Data (SIMD) stream |
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b. None of the above |
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c. Single Instruction Single Data (SISD) stream |
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d. Multiple Instruction Single Data (MISD) stream |
Feedback：
单指令单数据流
Question14
In a SMP system, each processor maintains a local cache and must alert all other processors that a change to cache update has taken place. This is referred to as the:
选择一个答案
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a. Cache coherency problem |
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b. Interconnection mechanism problem |
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c. None of the above |
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d. Synchronization mechanism problem |
Feedback：
高速缓存的一致性问题 P124
Question15
Key issues involved in the design of multiprocessor operating systems include:
选择一个答案
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a. All of the above |
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b. Synchronization |
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c. Scheduling |
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d. Reliability and fault tolerance |
Feedback：
P 125
Multiple Choice Questions 5
Question1
Concurrency plays a major part in which of the following specific contexts:
选择一个答案
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a. Multiple applications |
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b. All of the above √ |
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c. Structured applications |
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d. O/S structure |
Question2
In order to implement mutual exclusion on a critical resource for competing processes, only one program at a time should be allowed
选择一个答案
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a. In the critical section of the program √ |
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b. None of the above |
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c. To Exhibit cooperation |
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d. To perform message passing |
Question3
The following requirement must be met by any facility or capability that is to provide support for mutual exclusion:
选择一个答案
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a. All of the above √ |
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b. Only one process at a time can be allowed into a critical code section |
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c. A process remains in its critical code section for a finite time only |
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d. No assumptions can be made about relative process speeds |
Question4
Processes that are designed to be able to pass execution control back and forth between themselves are referred to as
选择一个答案
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a. None of the above |
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b. Threads |
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c. Coroutines √ |
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d. Busy waiting processes |
Question5
Processes that are designed to be able to pass execution control back and forth between themselves are referred to as
选择一个答案
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a. Coroutines √ |
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b. Threads |
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c. None of the above |
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d. Busy waiting processes |
Question6
In a uniprocessor system, mutual exclusion can be guaranteed by
选择一个答案
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a. Interleaving processes |
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b. Disabling interrupts √ |
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c. Overlapping processes |
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d. All of the above |
Question7
A semaphore that does not specify the order in which processes are removed from the queue is called a
选择一个答案
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a. Binary semaphore |
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b. Weak semaphore √ |
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c. None of the above |
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d. Strong semaphore |
Question8
The finite circular buffer is used to implement which of the following basic queuing strategies
选择一个答案
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a. LIFO |
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b. FILO |
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c. FIFO √ |
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d. None of the above |
Question9
A chief characteristic of a monitor is:
选择一个答案
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a. A maximum of two processes may be executing in a monitor at a time |
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b. All of the above |
|
c. Local data variables of the monitor are accessible by any procedure requesting use of the monitor |
|
d. A process enters the monitor by invoking one of its procedures √ |
Question10
In synchronization involving message passing, the sender of a message can be
选择一个答案
|
a. Only blocking |
|
b. All of the above |
|
c. Only non-blocking |
|
d. Either blocking or non-blocking √ |
Question11
In a system employing message passing, when a message is sent to a shared temporary data structure, this general approach is known as
选择一个答案
|
a. Direct addressing |
|
b. Blocking |
|
c. Indirect addressing √ |
|
d. None of the above |
Question12
In a system employing message passing, the typical message is divided into two primary sections
选择一个答案
|
a. None of the above √ |
|
b. Body and mailbox |
|
c. Destination ID and Source ID |
|
d. Header and mailbox |
Question13
The Reader/Writer problem requires that certain conditions be satisfied, such as:
选择一个答案
|
a. Any number of readers may simultaneously read from the file √ |
|
b. None of the above |
|
c. Readers may read from the file while writers are writing to it |
|
d. Multiple writers may write to the file simultaneouslyAny number of readers may simultaneously read from the file |
Question14
A reason why the Producer/Consumer problem cannot be considered a special case of the Reader/Writer problem with a single writer (the producer) and a single reader (the consumer) is:
选择一个答案
|
a. None of the above |
|
b. The Producer/Consumer problem doesn’t deal with concurrency issues |
|
c. The producer and consumer must be both reader and writer √ |
|
d. The consumer must perform writes while the reader performs reads |
Question15
Examples of solutions to the concurrency problem that do not involve busy waiting are the following:
选择一个答案
|
a. None of the above √ |
|
b. Semaphores and monitors |
|
c. Producers and consumers |
|
d. Message passing and caching |
Question16
A basic echo procedure (that echoes a typed character to the screen) running on a multiprocessor system can produce erroneous output if
选择一个答案
|
a. Two processes deadlock while in the echo code |
|
b. Access to the echo procedure is unsynchronized √ |
|
c. None of the above |
|
d. Access to the echo procedure is synchronized |
Multiple Choice Questions 6
Question1
The permanent blocking of a set of processes that either compete for system resources or communicate with each other is called:
选择一个答案
|
a. Starvation |
|
b. All of the above |
|
c. Prioritization |
|
d. Deadlock √ |
死锁是一组竞争系统资源或互相通信的竞争间相互的"永久"阻塞
Question2
In deadlocked process recovery, selection criteria for choosing a particular process to abort or rollback includes designating the process with the:
选择一个答案
|
a. Least total resources allocated so far |
|
b. Lowest priority |
|
c. All of the above √ |
|
d. Most estimated time remaining |
中文P196 死锁检测后恢复过程对“牺牲”进程的选择
Question3
One approach to an integrated strategy for dealing with deadlocks involves the implementation of:
选择一个答案
|
a. Process rollbacks |
|
b. Virtual memory |
|
c. Resource classes √ |
|
d. None of the above |
综合死锁策略：资源分类
Question4
The Dining Philosopher’s Problem is a standard test case for evaluating approaches to implementing:
选择一个答案
|
a. Synchronization √ |
|
b. Starvation |
|
c. All of the above |
|
d. Deadlock |
哲学家进餐问题是评价同步方法的一个测试标准
Question5
A software mechanism that informs a process of the occurrences of asynchronous events in UNIX are called:
选择一个答案
|
a. Pipes |
|
b. Messages |
|
c. Signals √ |
|
d. All of the above |
信号是用于通知发生一个同步事件的软件机制
Question6
Thread synchronization primitives supported by Solaris include:
选择一个答案
|
a. Condition variables |
|
b. Semaphores |
|
c. All of the above √ |
|
d. Mutual exclusion (mutex) locks |
互斥锁、信号量、多读者单写者锁、条件变量
Question7
The family of synchronization objects implemented by W2K include:
选择一个答案
|
a. Mutex objects |
|
b. Event objects |
|
c. All of the above √ |
|
d. Semaphore objects |
事件、互斥、信号量、可等待的计时器
Question8
All deadlocks involve conflicting needs for resources by:
选择一个答案
|
a. Three or more processes |
|
b. One or more processes |
|
c. None of the above |
|
d. Two or more processes √ |
两个或多个进程资源需求冲突
Question9
A resource that can be created and destroyed is called a:
选择一个答案
|
a. Reusable resource |
|
b. Producible resource |
|
c. Consumable resource √ |
|
d. All of the above |
可重用资源 VS 可消费资源
Question10
An example of a consumable resource is the following:
选择一个答案
|
a. All of the above |
|
b. Main Memory |
|
c. Messages √ |
|
d. Printers |
可创建可销毁的信息资源
Question11
A condition of policy that must be present for a deadlock to be possible is:
选择一个答案
|
a. Mutual exclusion |
|
b. No preemption |
|
c. All of the above √ |
|
d. Hold and wait |
三个必要条件
Question12
A direct method of deadlock prevention is to prevent the occurrence of:
选择一个答案
|
a. Hold and wait |
|
b. All of the above |
|
c. Circular wait √ |
|
d. Mutual exclusion |
死锁预防的直接法
Question13
In the Resource Allocation Denial approach to Deadlock Avoidance, a safe state is defined as one in which:
选择一个答案
|
a. At least one potential process sequence does not result in a deadlock √ |
|
b. None of the above |
|
c. All potential process sequences do not result in a deadlock: |
|
d. Several potential process sequences do not result in a deadlock: |
一条安全道路便可
Question14
A conservative strategy for dealing with deadlocks that involves limiting access to resources and imposing restrictions on processes is called:
选择一个答案
|
a. None of the above |
|
b. Deadlock Prevention √ |
|
c. Deadlock Detection |
|
d. Deadlock Avoidance |
资源预防
Multiple Choice Questions 7
Question1
The task of subdividing memory between the O/S and processes is performed automatically by the O/S and is called:
选择一个答案
|
a. All of the above |
|
b. Protection |
|
c. Memory Management √ |
|
d. Relocation |
内存管理
Question2
A reference to a memory location independent of the current assignment of data to memory is called a:
选择一个答案
|
a. Absolute address |
|
b. None of the above |
|
c. Logical address √ |
|
d. Relative address |
逻辑地址的定义
Question3
An actual location in main memory is called a:
选择一个答案
|
a. Relative address |
|
b. Absolute address √ |
|
c. Logical address |
|
d. None of the above |
物理地址即绝对地址
Question4
The page table for each process maintains:
选择一个答案
|
a. None of the above |
|
b. The frame location for each page of the process √ |
|
c. The physical memory location of the process |
|
d. The page location for each frame of the process |
页号对应帧号
Question5
In a system employing a paging scheme for memory management, wasted space is due to:
选择一个答案
|
a. Internal fragmentation √ |
|
b. Pages and frames of different specified sizes |
|
c. None of the above |
|
d. External fragmentation |
固定分区和分页都产生内部碎片
Question6
In a system employing a segmentation scheme for memory management, wasted space is due to:
选择一个答案
|
a. Internal fragmentation |
|
b. External fragmentation √ |
|
c. None of the above |
|
d. Segments of different sizes |
动态分区和分段都产生外部碎片
Question7
In a system employing a segmentation scheme for memory management, a process is divided into:
选择一个答案
|
a. A number of segments which must be of equal size |
|
b. None of the above |
|
c. A number of segments which need not be of equal size √ |
|
d. One segment per thread |
分段：多个大小不等的块
Question8
The concept of Memory Management satisfies certain system requirements, including:
选择一个答案
|
a. Relocation |
|
b. Physical organization |
|
c. All of the above √ |
|
d. Protection |
重定位、保护、共享、逻辑组织、物理组织
Question9
The practice in which a program and data are organized in such a way that various modules can be assigned the same region of memory is called:
选择一个答案
|
a. Sharing |
|
b. None of the above |
|
c. Overlaying √ |
|
d. Relocation |
覆盖
Question10
The concept of virtual memory is based on one or both of two basic techniques:
选择一个答案
|
a. Segmentation and paging √ |
|
b. None of the above |
|
c. Overlaying and relocation |
|
d. Segmentation and partitioning |
虚拟=>分段分页
Question11
A problem with the largely obsolete Fixed Partitioning memory management technique is that of:
选择一个答案
|
a. Inefficient use of memory |
|
b. Internal fragmentation |
|
c. Allowing only a fixed number of Processes |
|
d. All of the above √ |
Question12
The problem of internal fragmentation can be lessened in systems employing a fixed-partition memory management scheme by using:
选择一个答案
|
a. Unequal size partitions √ |
|
b. Random size partitions |
|
c. Equal size partitions |
|
d. None of the above |
分段解决内部碎片，但是会引入外部碎片
Question13
In the Dynamic Partitioning technique of memory management, the phenomenon that results in unused blocks of memory outside of existing partitions is called:
选择一个答案
|
a. Compaction |
|
b. Internal fragmentation |
|
c. None of the above |
|
d. External fragmentation √ |
动态分区 外部碎片
Question14
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:
选择一个答案
|
a. All of the above |
|
b. Next-fit |
|
c. First-fit |
|
d. Best-fit √ |
最佳适配，首次适配，邻近适配
Question15
In the Dynamic Partitioning technique of memory management, the placement algorithm that scans memory from the location of the last placement and chooses the next available block that large enough to satisfy the request is called:
选择一个答案
|
a. First-fit |
|
b. All of the above |
|
c. Best-fit |
|
d. Next-fit √ |
Multiple Choice Questions 8
Question1
The type of memory that allows for very effective multiprogramming and relieves the user of memory size constraints is referred to as:
选择一个答案
|
a. Virtual memory √ |
|
b. Real memory |
|
c. Main memory |
|
d. All of the above |
Question2
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:
选择一个答案
|
a. Least recently used (LRU) policy |
|
b. Clock policy |
|
c. Optimal policy √ |
|
d. None of the above |
Question3
The replacement policy that chooses only among the resident pages of the process that generated the page fault in selecting a page to replace is referred to as a:
选择一个答案
|
a. Local replacement policy √ |
|
b. Variable replacement policy |
|
c. Global replacement policy |
|
d. None of the above |
Question4
The concept associated with determining the number of processes that will be resident in main memory is referred to as:
选择一个答案
|
a. A cleaning policy |
|
b. Load Control |
|
c. None of the above |
|
d. The page fault frequency √ |
Question5
In SVR4 and Solaris systems, the memory management scheme that manages user processes and disk I/O is called the:
选择一个答案
|
a. Paging system √ |
|
b. None of the above |
|
c. Virtual memory manager |
|
d. Kernel memory allocator |
Question6
The multilevel memory management scheme implemented in Linux was designed to minimize large page tables and directories in which of the following line of processors:
选择一个答案
|
a. 32-bit Pentium/X86 architecture |
|
b. 16-bit X86 architecture |
|
c. 64-bit Alpha architecture √ |
|
d. None of the above |
Question7
The Windows 2000 virtual memory manager can use page sizes ranging from:
选择一个答案
|
a. 64 KB to 4 GB |
|
b. None of the above |
|
c. 4 KB to 64 KB √ |
|
d. 4 GB to 4 TB |
Question8
The situation where the processor spends most of its time swapping process pieces rather than executing instructions is called:
选择一个答案
|
a. Paging |
|
b. The Principle of Locality |
|
c. None of the above |
|
d. Thrashing √ |
Question9
The situation that occurs when the desired page table entry is not found in the Translation Lookaside Buffer (TLB) is called a:
选择一个答案
|
a. None of the above |
|
b. TLB hit |
|
c. TLB miss √ |
|
d. Page fault |
Question10
The real address of a word in memory is translated from the following portions of a virtual address:
选择一个答案
|
a. None of the above |
|
b. Frame number and offset |
|
c. Page number and frame number |
|
d. Page number and offset √ |
Question11
Segmentation has a number of advantages to the programmer over a non-segmented address space, including:
选择一个答案
|
a. Sharing among processes |
|
b. Simplifying the handling of growing data structures |
|
c. All of the above √ |
|
d. Protection |
Question12
In a combined paging/segmentation system, a user’s address space is broken up into a number of:
选择一个答案
|
a. Fixed-size pages, which are in turn broken down into variable-sized segments |
|
b. Segments or pages, at the discretion of the programmer |
|
c. Variable-sized Segments, which are in turn broken down into fixed-size pages √ |
|
d. All of the above |
Question13
Sharing is achieved in a segmentation system by:
选择一个答案
|
a. Having a common data area that all processes can share |
|
b. Referencing a segment in the segment tables of more than one process √ |
|
c. All of the above |
|
d. Each process segment table having a reference to the dispatcher main memory area |
Question14
A fundamental choice in the design of the memory-management portion of an O/S is:
选择一个答案
|
a. Whether or not to use virtual memory techniques |
|
b. All of the above √ |
|
c. Whether to use paging, segmentation of a combination of the two |
|
d. The algorithms employed for various aspects of memory management |
Question15
The fetch policy that exploits the characteristics of most secondary memory devices, such as disks, which have seek time and rotational latency is called:
选择一个答案
|
a. Swapping |
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b. Demand paging |
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c. Prepaging √ |
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d. None of the above |
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Multiple Choice Questions 9
Question1 The type of scheduling that involves the decision to add a process to those that are at least partially in main memory and therefore available for execution is referred to as: 选择一个答案
Question2 One difficulty with the Shortest Process Next (SPN) scheduling technique is: 选择一个答案
Question3 One difficulty with the Shortest Remaining Time (SRT) scheduling technique is: 选择一个答案
Question4 Which of the following scheduling policies require prior knowledge or estimation of process length: 选择一个答案
Question5 It is impossible to make definitive comparisons of various scheduling policies due to dependence on factors such as: 选择一个答案
Question6 The strategy that schedules processes based on their group affiliation is generally referred to as: 选择一个答案
公平共享 Question7 The traditional UNIX scheduler divides processes into fixed bands of priority levels, with the highest priority band being the: 选择一个答案
Question8 The decision as to which job to admit to the system next can be based on which of the following criteria: 选择一个答案
Question9 Typically, the swapping-in function for processes is based on the need to manage: 选择一个答案
Question10 In terms of frequency of execution, the short-term scheduler is usually the one that executes: 选择一个答案
Question11 Response time in an interactive system is an example of: 选择一个答案
Question12 A typical way to overcome starvation of lower-priority processes in a priority-based scheduling system is to: 选择一个答案
Question13 Which of the following scheduling policies allow the O/S to interrupt the currently running process and move it to the Ready state? 选择一个答案
Question14 In terms of the queuing model, the total time that a process spends in a system (waiting time plus service time) is called: 选择一个答案
Question15 In the Round Robin scheduling technique, the principle design issue is: 选择一个答案
Multiple Choice Questions 10 Question1 An example of the key differences that can exist across (and even in) classes of I/O devices is: 选择一个答案
Question2 The following disk scheduling policy is useful as a benchmark against which to evaluate other disk scheduling policies because it provides a worst-case scenario: 选择一个答案
Question3 The disk scheduling algorithm that implements two subqueues in a measure to avoid the problem of “arm stickiness” is the: 选择一个答案
Question4 Which of the following RAID levels implement some form of parity calculation to introduce redundancy: 选择一个答案
Question5 The disk cache replacement strategy that replaces the block that has experienced the fewest references is called: 选择一个答案
Question6 In a UNIX system, which of the following types of I/O devices make use of character queues: 选择一个答案
Question7 In a W2K system, the I/O manager module that includes lazy write and lazy commit services to improve overall performance is the: 选择一个答案
Question8 The I/O technique where the processor busy waits for an I/O operation to complete is called: 选择一个答案
Question9 The system configuration that includes an I/O module which is a separate processor with a specialized instruction set can be referred to using the following terminology: 选择一个答案
Question10 The bus configuration for DMA that provides no path other than the system bus between the DMA module(s) and I/O devices is: 选择一个答案
Question11 The primary objective in designing the I/O facility of a computer system that deals with the desire to handle all I/O devices in a uniform manner is referred to as: 选择一个答案
Question12 In a hierarchical structure for managing I/O on a secondary storage device that supports a file system, the layer that is closest to the hardware is the: 选择一个答案
Question13 An example of a block-oriented I/O device is: 选择一个答案
Question14 The scenario where multiple buffers are used in an attempt to alleviate the problem of absorbing rapid bursts of I/O is typically referred to as: 选择一个答案
|
Multiple Choice Questions 11
Question1
A file is generally defined to be:
选择一个答案
|
a. All of the above |
|
b. A collection of related fields |
|
c. A basic element of data |
|
d. A collection of similar records √ |
Question2
Fixed file blocking experiences the following potential problem:
选择一个答案
|
a. External fragmentation |
|
b. None of the above |
|
c. Internal fragmentation √ |
|
d. Gaps due to hardware design |
Question3
In which of the following file allocation methods is preallocation required:
选择一个答案
|
a. Indexed |
|
b. None of the above |
|
c. Chained |
|
d. Contiguous √ |
Question4
The technique of free disk space management that employs a pointer and length value of each free portion is the:
选择一个答案
|
a. None of the above √ |
|
b. Free block list |
|
c. Bit tables |
|
d. Indexing |
Question5
The data structure that maintains information on available disk space is called the:
选择一个答案
|
a. File Allocation Table (FAT) |
|
b. None of the above |
|
c. Bit Table |
|
d. Disk Allocation Table √ |
Question6
File allocation in a UNIX system has the following characteristics:
选择一个答案
|
a. Dynamic allocation using non-contiguous blocks with indexing √ |
|
b. Preallocation using non-contiguous blocks without indexing |
|
c. None of the above |
|
d. Dynamic allocation using contiguous blocks without indexing |
Question7
In a W2K NTFS file system, the smallest physical storage unit on the disk (almost always 512 bytes) is called a:
选择一个答案
|
a. Cluster |
|
b. Volume |
|
c. Sector √ |
|
d. None of the above |
Question8
The level of the file system architecture that enables users and applications to access file records is called the:
选择一个答案
|
a. Logical I/O level √ |
|
b. All of the above |
|
c. Basic I/O supervisor level |
|
d. Basic file system level |
Question9
Record access in a pile file can be conducted by:
选择一个答案
|
a. Key field |
|
b. All of the above |
|
c. Exhaustive search √ |
|
d. Partial index |
Question10
Sequential files are optimal in scenarios involving:
选择一个答案
|
a. Applications that require infrequent updates |
|
b. All of the above |
|
c. Applications that require frequent queries |
|
d. Applications that require the processing of all records in the file √ |
Question11
Indexed sequential files similar to sequential files, but contain two added features:
选择一个答案
|
a. File index and overflow file √ |
|
b. Hash function and an overflow file |
|
c. All of the above |
|
d. Hash function and file index |
Question12
Direct or hashed files are often used where:
选择一个答案
|
a. Fixed length records are used |
|
b. All of the above √ |
|
c. Very rapid access is required |
|
d. Records are always accessed one at a time |
Question13
The file directory information element that holds information such as the identity of the creator of the file is the:
选择一个答案
|
a. All of the above |
|
b. Address information element |
|
c. Usage information element √ |
|
d. Access control information element |
Question14
In a tree-structured directory, the series of directory names that culminates in a file name is referred to as the:
选择一个答案
|
a. Pathname √ |
|
b. Working directory |
|
c. None of the above |
|
d. Symbolic name |
Question15
Access rights on a file typically are considered to constitute a hierarchy, with each right implying those that:
选择一个答案
|
a. Precede it √ |
|
b. Succeed it |
|
c. None of the above |
|
d. Supercede it |
