ch1 review Silberschatz operating systems essentials concepts 2nd ed

Review Questions
Section 1.1
1.1 What are the four components of a computer system?a computer system can be divided roughly into four components:the hardware, the operating system, the application programs, and the users.
1.2 Provide at least three resources the operating system allocates.  The hardware -the cpu, the memory,and the input/output devices-provide the basic computing resources for the system.
1.3 What is the common name used to refer to the operating system program? resource allocator
1.4 What do mobile operating systems often include in addition to the core kernel? middleware
Section 1.2
1.5 What is an interrupt? a signal sent to the cpu to initiate the execution of a process.
1.6 What special operation triggers a software interrupt? system call
1.7 What is one advantage of using a solid state disk over a magnetic disk? zero moving parts
1.8 What is the difference between volatile and nonvolatile storage? volatile memory loses its contents when there is a loss of power to the system. nonvolatile retains the data in the event of loss of power to the system.
Section 1.3
1.9 What is another term for multiprocessor system? parallel systems or multicore systems
1.10 Provide at least two advantagesof multiprocessor systems. economy of scale, increased reliability, and increased throughput
1.11 True or False? The most common multiple-processor system uses asymmetric multiprocessing. false
1.12 What is the name of a multiprocessor system that uses multiple computing cores? multicore
1.13 How does a clustered system differ from a multicore system? clustered systems are multiprocessor systems comprised of two or more individual systems or nodes joined together.
Section 1.4
1.14 How does multiprogramming increase CPU utilization? these systems organize jobs so that the cpu always has a task to execute.
1.15 What is the term for a program that has been loaded and is executing? a process
1.16 What part of the operating system makes the decision with regards to which job will run? cpu
Section 1.5
1.17 What are the two separate modes of operation? user mode and kernel mode
1.18 What is the mode of the system at boot time? in kernel mode
1.19 What is the mode of the system when the operating system gains control? user mode
1.20 What is the mode of the system when a user program is running? user mode
Section 1.6
1.21 Name at least two activities the operating system is responsible for in connection with process management. scheduling processes and threads on the cpus, suspending and resuming processes, creating and deleting user and system processes, providing mechanisms for process communication, as well as process synchronization
Section 1.7
1.22 Name at least two activities the operating system is responsible for in connection with memory management. the operating system is responsible for keeping track of which parts of memory are currently being used and who is using them; deciding which processes (or parts of processes) and data to move into and out of memory; as well as allocating and deallocating memory space as needed
Section 1.8
1.23 True or False? Managing files is one of the most visible aspects of an operating system. true
1.24 Name at least two activities the operating system is responsible for in connection with file management. creating and deleting files; creating ad deleting directories to organize files; supporting primitives for manipulating files and directories; mapping files onto secondary storage; backing up files on stable (nonvolatile) storage media
1.25 Name at least two activities the operating system is responsible for in connection with disk management. free-space management; storage allocation; disk scheduling
1.26 Of the following five forms of storage, rank them from fastest to slowest in terms of access time:
(1)mainmemory, (2)magneticdisk, (3)registers, (4) solid state disk, (5) cache.
registers(0.25-0.5)
cache(0.5-25)
main memory(80-250)
solid state disk(25,000-50,000)
hard disk(5,000,000)
Section 1.9
1.27 What is the difference between protection and security? protection is any mechanism for controlling the access of processes or users to the resources defined by a computer system.it is the jobof security to defend a system from external and internal attacks.
Section 1.10
1.28 List at least four common kernel data structures. arrays, lists, stacks, queues, trees, hash functions, and maps
1.29 True or False? A bitmap of length N can be used to represent the status of 2N items. False
Section 1.11
1.30 List at least five different types of computing environments. Traditional; Mobile; Distributed Systems; Client Server Computing; Peer-to-Peer Computing; Virtialization; Cloud Computing; Real-Time Embedded Systems
Section 1.12
1.31 Provide an example of an open source operating system. Linux, bsd Unix, and Solaris are all open source.