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Terms in this set (720)T/F: The client-based station generally presents the type of graphical interface that is most comfortable to users, including the use of windows and a mouse. True T/F: Each server in the client/server environment provides a set of shared services to the clients. True T/F: The key feature of a client/server architecture is the allocation of application-level tasks between clients and servers. True T/F: The client is responsible for maintaining the database, for which purpose a complex database management system software module is required. False T/F: The communications software is what enables client and server to interoperate. True T/F: Host-based processing is true client/server computing. False T/F: Cooperative processing enables the user to employ applications tailored to local needs. False T/F: The dual caching approach is used to reduce communications traffic (client cache) and disk I/O (server cache). True T/F: Blocking primitives provide for efficient, flexible use of the message-passing facility by processes. False T/F: A reliable message-passing facility is one that guarantees delivery if possible. True T/F: Virtually all application processing may be done at the client, with the exception of data validation routines and other database logic functions that are best performed at the server. True T/F: The fat client approach mimics the traditional host-centered approach and is often the migration path for evolving corporate-wide application from the mainframe to a distributed environment False T/F: The procedure call is used for access to remote services. True T/F: The Beowulf approach is widely implemented and is perhaps the most important cluster technology available. True T/F: A cluster is easier than an SMP to manage and configure. False A set of function and call programs that allow clients and servers to intercommunicate is a(n) ________ interface. A) SQL D The most basic class of client/server configuration is __________ , in which the client is principally responsible for providing a graphical user interface, while virtually all of the processing is done on the server. A) host-based processing C A networked information requester, usually a PC or workstation, that can query database and/or other information from a server is a(n) _________ A) client B) cluster C) API D) SQL A The _________ enables many clients to share access to the same database and enables the use of a high-performance computer system to manage the database. A) relational database B
__________ is a set of drivers, APIs, or other software that improves connectivity between a client application and a server. A) Distributed message passing D _________ processing refers to the traditional mainframe environment in which all, or virtually all, of the processing is done on a central host. A) Host-based B) Cooperative C) Server-based D) Client-based A The ________ processing architecture is the most common client/server approach in current use. A) server-based B) client-based C) host-based D) cooperative B As a result of _________ , common functions can be used by different departments internally and by external business partners as well. A) middleware B A __________ is a specific kind of service provider that acts as a registry and allows for the lookup of service provider interfaces and service locations. A) Service requestor D A _________ is a group of interconnected, whole computers working together as a unified computing resource that can create the illusion of being one machine. A) SMP B) node C) cluster D) single-system C With the _________ clustering method, data are continuously copied from primary to secondary server. A) separate server A The function of switching an application and data resources over from a failed system to an alternative system in the cluster is referred to as __________ . A) failsafe B) failnode C) failback D) failover D In the _________ approach, the programmer writes the application from the outset to run on a cluster and uses message passing to move data, as required, between cluster nodes. A) passive standby B The common disks are partitioned into volumes, and each volume is owned by a single computer, is the _________ approach. A) shared disk D Pvmsync, EnFuzion, and BPRoc are examples of __________ system software. A) Graphical User Interface D The _________ machines are generally single-user PCs or workstations that provide a highly user-friendly interface to the end user. client A __________ is a computer, usually a high-powered workstation, a minicomputer, or a mainframe, that houses information for manipulation by networked clients. server A __________ is a database in which information access is limited to the selection of rows that satisfy all search criteria. relational database _________ is a language developed by IBM and standardized by ANSI for addressing, creating, updating, or querying relational databases. Structured Query Language (SQL) In addition to clients and servers, the third essential ingredient of the client/server environment is the _________ . network In a _________ configuration, the application processing is performed in an optimized fashion, taking advantage of the strengths of both client and server machines and of the distribution of data. cooperative processing The main benefit of the ________ model is that it takes advantage of desktop power, offloading application processing from servers and making them more efficient and less likely to be bottlenecks. fat client In a _________ architecture, the application software is distributed among three types of machines: a user machine, a middle-tier server, and a backend server. three-tier The essence of the _________ technique is to allow programs on different machines to interact using simple procedure call/return semantics, just as if the two programs were on the same machine. remote procedure call (RPC) The restoration of applications and data resources to the original system once it has been fixed is referred to as __________ . failback The problem of keeping local cache copies up to date to changes in remote data is known as the _________ problem. cache consistency "Servers are cabled to the same disks, but each server owns its disks. If one server fails, its disks are taken over by the other server," is a description of the _________ clustering method. servers connected to disks The basic purpose of _________ is to enable an application or user at a client to access a variety of services on servers without being concerned about differences among servers. middleware __________ is a shared-nothing cluster, in which each disk volume and other resources are owned by a single system at a time. Windows Failover clustering The goal of __________ was to investigate the potential of clustered PCs for performing important computation tasks beyond the capabilities of contemporary workstations at minimum cost. Beowulf T/F: An OS associates a set of privileges with each process True T/F: The misfeasor is generally an outsider. False T/F: The objective of the intruder is to gain access to a system or to increase the range of privileges accessible on a system. True T/F: Worms and bot programs are self-contained programs that can be scheduled and run by the operating system. True T/F: Intrusion detection systems are only designed to detect malicious software behavior. False T/F: The needs and policy relating to backup and archive should be determined during the final stages of implementation False T/F: Firewalls are traditionally configured to limit access by port or protocol, from some or all external systems. True T/F: The owner of the object can generally perform any action on the security descriptor True T/F: The Security ID identifies a user uniquely across all of the machines on the network. True T/F: Manual analysis of logs is preferred, as it is more likely to identify abnormal activity. False T/F: All users with access to a system will have the same access to all data and resources on that system. False T/F: Host-based firewalls, IDS, and IPS software also may improve security True T/F: You should stage and validate all patches on test systems before deploying them in production. True T/F: The superuser is exempt from the usual file access control constraints and has systemwide access. True T/F: DAC is based on the roles that users assume in a system rather than the user's identity. True On a typical system the highest level or privilege is referred to as _________ . A) administrator D A _________ is an individual who is not authorized to use the computer and who penetrates a system's access controls to exploit a legitimate user's account. A) clandestine user C A __________ is an individual who seizes supervisory control of the system and uses this control to evade auditing and access controls or to suppress audit collection. A) misfeasor B A _________ is a legitimate user who accesses data, programs, or resources for which such access is not authorized, or who is authorized for such access but misuses his or her privileges. A) superuser B The ________ determines which users and groups can access this object for which operations. A) DACL B) SACL C) RPC D) ACE A ________ define the type and contents of a security descriptor. A) SACLs B) Flags C) Owners D) DACLs B ________ is the identifier by which this user is known to the system for purposes of security. A) ACE B) Access token C) SID D) Password scheme C
Effective _________ helps ensure that in the event of a system breach or failure, system administrators can more quickly and accurately identify what happened and thus most effectively focus their remediation and recovery efforts. A) logging B) archiving C) security D) patching A ________ is the traditional method of implementing access control. A) MAC B) RAC C) DAC D) RBAC C ________ controls access based on comparing security labels with security clearances. A) RBAC B) MAC C) DAC D) RAC B _________ defenses aim to harden programs to resist attacks. A) Coding B) Compile-time C) Runtime D) Programming B
A __________ is a dedicated computer that interfaces with computers outside a network and has special security precautions built into it in order to protect sensitive files on computers within the network. A) firewall A _________ implements a security policy that specifies who or what may have access to each specific system resource and the type of access that is permitted in each instance. A) Guard page B Recognition by voice pattern, handwriting characteristics, and typing rhythm are examples of ________ . A) cyclical biometrics C
Recognition by fingerprint, retina, and face are examples of ___________ . A) static biometrics A With ________ a process has complete control of the system and can add or change programs and files, monitor other processes, send and receive network traffic, and alter privileges. root access A key security issue in the design of any _________ is to prevent, or at least detect, attempts by a user or a piece of malicious software from gaining unauthorized privileges on the system. operating system System access threats fall into two general categories: intruders and ________ malicious software The three classes of intruders are: clandestine user, misfeasor, and ________ . masquerader Intrusion detection systems can be classified as host-based or ___________ . network based _______ is the process of retaining copies of data over extended periods of time in order to meet legal and operational requirements to access past data. archive _______ is the process of making copies of data at regular intervals, allowing the recovery of lost or corrupted data over relatively short time periods. backup System security begins with the installation of the _________ . operating system ________ defenses aim to detect and abort attacks in executing programs. Runtime __________ is a condition at an interface under which more input can be placed into a buffer or data-holding area than the capacity allocated, overwriting other information. buffer overflow _________ controls access based on the roles that users have within the system and on rules stating what accesses are allowed to users in given roles. RBAC (role based access control) _________ controls access based on the identity of the requestor and on access rules stating what requestors are or are not allowed to do. DAC (discretionary access control) The design goals for a ________ are: acts as a choke point, enforces the local security policy, is secure against attacks. firewall Electronic keycards, smart cards, and physical keys are authenticators that are referred to as a __________ . token An IDS comprises three logical components: sensors, user interface, and ________ . analyzers T/F: Virtualization technology enables a single PC or server to simultaneously run multiple operating systems or multiple sessions of a single OS. True T/F: VMM allows multiple VMs to safely coexist on a single physical server host and share that host's resources. True T/F: The hyperfile sits between the hardware and the VMs and acts as a resource broker. False T/F: There are currently more virtual servers deployed in the world than physical servers. True T/F: A key aspect of server virtualization is that VMs cannot be viewed as network resources False T/F: Virtual Machine technologies are also used in desktop environments to run multiple operating systems. True T/F: A virtual server sees all of the resources of the physical host. False T/F: Once the virtual machine is created it can be powered on like a physical server and utilized in the manner of a physical server. True T/F: Virtual machines are made up of files. True T/F: Type-2 hypervisors are considered to be more secure than the Type-1 hypervisors. False T/F: Adding additional vCPUs in a VM is a difficult and time-consuming process. False T/F: Protection rings describe level of access or privilege inside of a computer system. True T/F: The process of reclaiming older pages that are not being used is done through ballooning True
T/F: The disadvantage to a directly connected I/O device is that the virtual machine is tied to the physical server it is running on. True T/F: Virtual machines are hosted via the infrastructure services in the VMkernel True The solution that enables virtualization is a __________ . A) round robin B The number of guests that can exist on a single host is measured as a ________ . A) VMM ratio C The _________ approach is becoming a common way for businesses and individuals to deal with legacy applications and to optimize their hardware usage. A) virtual machine A The ________ facilitates the translation and I/O from the virtual machine to the physical server devices. A) hardware C There are _______ types of hypervisors, distinguished by whether there is another operating system between the hypervisor and the host. A) two B) three C) four D) five A A ________ hypervisor has much better performance characteristics than the Type-2 hypervisor. A) Type-1 B) Type-3 C) Type-4 D) Type-5 A User applications run in ______ which is the least trusted area. A) Ring 0 B) Ring 1 C) Ring 2 D) Ring 3 D Hypervisors run in ________ controlling hardware access for the virtual machines they host. A) Ring 0 B) Ring 1 C) Ring 2 D) Ring 3 A _______ is a commercially available hypervisor from VMware that provides users a bare metal hypervisor to host virtual machines on their servers. A) Zygote B) Dalvi06B C) JVM D) ESXi D ________ permits the relocation of the data files that compose a virtual machine while that virtual machine is in use. A) DRS B _________ can power-off and on physical hosts as they are needed. A) Storage and Network I/O Control C ________ uses various replication technologies to copy selected virtual machines to a secondary site in the case of a data center disaster. A) Site Recovery Manager A The ________ is a process running on a DVM that is launched at boot time. A) Zygote B) Java VM C) Xen D) Dalvik A A standard Java compiler turns source code into bytecode, which is then compiled into a _______ file that the Dalvik VM can read and use. A) .jar B) .dex C) .apk D) .class B The concept of _________, as used in Linux, refers to a partitioning of the privileges available to a root user. A) root isolation C A machine with _________ software can host numerous applications, including those that run on different operating systems, on a single platform.
virtualization A VMM is commonly known today as a ________ hypervisor The _________ , or hypervisor, abstracts the physical hardware from the virtual machines it supports. virtual machine monitor A ________ is a software construct that mimics the characteristics of a physical server. Virtual machine An operating system in a virtual machine accesses the resource that is presented to it by the Virtual Machine Monitor or _________ . hypervisor VMware Workstation and Oracle VM Virtual Box are examples of ________ hypervisors. Type-2 ________ is a software-assisted virtualization technique that uses specialized APIs to link virtual machines with the hypervisor to optimize their performance. Paravirtualization When multiple VMs are contending for a processor, the ________ acts as the traffic controller, scheduling processor time for each VM's request as well as directing the requests and data to and from the virtual machines. hypervisor The _________ is the central router of information and controls access to all of the physical resources of the hardware. operating system Ring _______ is the most trusted layer and is where the operating system kernel works and can interact directly with hardware. 0 (zero) Similar to data de-duplication, __________ is a feature built into hypervisors that help optimize memory usage. page sharing The capability to allocate more memory than physically exists on a host is called __________ . memory overcommit _________ creates a lockstep copy of a virtual machine on different host so that if the original host suffers a failure, the virtual machine's connections get shifted to the copy without interrupting users or the application they are using. Fault tolerance The goal of a __________ is to provide a runtime space for a set of Java code to run on any operating system staged on any hardware platform, without needing to make code changes to accommodate the different operating systems or hardware. java virtual machine The Android platform's virtual machine is referred to as ________ . Dalvik T/F: Embedded systems can be part of a larger system or product. True T/F: Typically, more complex embedded systems do not include an OS. False T/F: An antilock braking system in a car is an example of an embedded system. True T/F: General-purpose computer systems far outnumber embedded systems. False T/F: A simple embedded system, with simple functionality, may be controlled by a special-purpose program or set of programs with no other software. True T/F: General-purpose operating systems typically permit any user process to use interrupts directly. False T/F: The disadvantage of using a general-purpose OS is that it is not optimized for real-time and embedded applications. True T/F: "Has a slow and lightweight process or thread switch" is a typical characteristic of a specialized embedded OS. False T/F: The eCos system provides a more streamlined approach for an embedded OS than one based on a commercial general-purpose OS. True T/F: Android is an embedded OS based on a Linux kernel True T/F: Embedded software does not execute in response to external events. False T/F: The TinyOS scheduler operates across all components True T/F: A key differentiator between desktop/server and embedded Linux distributions is that desktop and server software is typically compiled on one platform but is intended to be executed on another. False T/F: To deal with timing constraints the kernel maintains a real-time clock. True T/F: A mutex is used to enforce mutually exclusive access to a resource, allowing only one thread at a time to gain access. True __________ refers to the use of electronics and software within a product. A) TinyOS C _________ is one of the most widely used embedded operating systems. A) API B) eCos C) TinyOS D) MQS B A key design requirement for _________ is portability to different architectures and platforms with minimal effort. A) HAL B) TinyOS C) GNU D) none of the above D Configurability, direct use of interrupts, I/O device flexibility, and real-time operation are some of the unique
characteristics and design requirements for __________ . C Two examples of operating systems that have been designed from the ground up for embedded applications are TinyOS and _________ . A) eCos B) Linux C) BSD D) HAL A The __________ module contains the code necessary for processor startup, interrupt delivery, context switching, and other functionality specific to the instruction set architecture of that processor family. A) Variant D The __________ module includes code for startup, chip selection configuration, interrupt controllers, and timer devices. A) Architecture B) Variant C) MMU D) Platform D _________ in TinyOS may be tied either directly or indirectly to hardware events. A) Commands B) Tasks C) Timers D) Events D _________ is an advantage of using Linux as the basis for an embedded OS. A) Vendor independence D __________ are the clients of the driver. A) DSRs B) ISRs C) Threads D) I/O systems C __________ has become a popular approach to implementing wireless sensor network software. A) eCos B) TinyOS C) Arbiter D) Embedded system B Each _________ in a component is similar to a thread in an ordinary OS, with certain limitations. A) kernel B) command C) event D) task D The __________ interface allows the client to hold on to a resource until the client is notified that someone else needs the resource. A) Resource configure B Once a client has access to a resource, it uses ___________ to exchange data and control information with the resource. A Operate with limited resources, adapt to hardware evolution, support a wide range of applications, support a diverse set of platforms, and be robust are goals for __________ . A) TinyOs B) eCos C) DSRs D) ISRs A __________ are a combination of computer hardware and software designed to perform a dedicated function Embedded systems The _________ provides a more streamlined approach for an embedded OS than one based on a commercial general-purpose OS, such as an embedded version of Linux. Embedded Configurable Operating System (eCos) An embedded software system built using TinyOS consists of a set of small modules, called _________ , each of which performs a simple task or set of tasks and which interface with each other and with hardware in limited and well-defined ways. components In TinyOS, __________ are nonblocking requests. commands The default scheduler in TinyOS is a simple __________ queue. first in first out (FIFO) The ________ component mediates data exchange between the client and the underlying resource. Shared resource The _________ accepts requests for access and configuration from a client and enforces the lock on the underlying resource. Arbiter Real-time operation, reactive operation, configurability, I/O device flexibility, and streamlined protection mechanisms are characteristics and design requirements for __________ systems. embedded operating An existing commercial OS can be used for an embedded system by adding ________ capability, streamlining operation, and adding necessary functionality. real time ________ is a compressed, read-only file system that was designed for use on low memory or limited storage size environments such as embedded Linux systems. Squashfs The _________ is a simple, read-only file system that is designed to minimize size by maximizing the efficient use of underlying storage. cramfs Three abstractions for resources are used in TinyOS: dedicated, virtualized, and ________ . shared Interrupts and counters are examples of ________ abstractions. dedicated A clock or timer is an example of the _________ abstraction. virtualized The shared resource configuration provides the following interfaces to a client: Resource, Resource requested, ________ , and resource-specific interfaces. resource configure T/F: All types of UNIX files are administered by the OS by means of inodes. True T/F: A preallocation policy requires that the maximum size of a file be declared at the time of the file creation request. True T/F: File systems do not maintain the attributes associated with the files. False T/F: A field is characterized by its length and data type. True T/F: The cluster is the fundamental unit of allocation in NTFS. True T/F: Records may only be of fixed length. False
T/F: The superuser is exempt from the usual file access control constraints and has system wide access True T/F: Typically, the only way that a user or application may access files is through the file management system. True T/F: Device drivers are not part of the operating system. False T/F: The least-complicated form of file organization is the indexed file. False T/F: The sequential file organization is the only one that is easily stored on tape as well as disk. True T/F: A partial index contains one entry for every record in the main file. False T/F: A file directory contains information about the files, including attributes, location, and ownership. True T/F: Indexed allocation supports both sequential and direct access to the file and thus is the most popular form of file allocation. True T/F: A file allocation table (FAT) is used to keep track of the portions assigned to a file. True A _________ is the basic element of data. A) database B) field C) file D) record B A __________ is responsible for starting I/O operations on a device and processing the completion of an I/O request. A) basic I/O supervisor C A _________ is a collection of related fields that can be treated as a unit by some application program. A) file B) field C) record D) database C An objective of the __________ is to provide a standardized set of I/O interface routines to user processes. A) working
directory B A __________ is a collection of similar records. A) file B) database C) record D) field A The __________ level is the primary interface with the environment outside of the computer system. A) logical I/O C _________ are used mostly in applications where timeliness of information is critical and where data are rarely processed exhaustively. A) Indexed files A A _________ is a collection of related data. A) record B) file C) database D) field C The _________ is concerned with scheduling disk and tape accesses to optimize performance. A) device driver B The term _________ refers to the logical structuring of the records as determined by the way in which they are accessed. A) file organization A The most common form of file structure is __________ . A) the indexed file B The _________ file exploits the capability found on disks to access directly any block of a known address. A) direct A A _________ is a contiguous set of allocated blocks. A) key B) pathname C) pile D) portion D The _________ contains the core parts of the operating system, including system binaries, system libraries, and configuration files. A) data directory B __________ represents an open file associated with a process. A) Dentry object C
A UNIX file system resides on a single logical disk or disk partition and is laid out with the following elements: superblock, inode table, data blocks, and __________ . boot block The __________ level provides a standard interface between applications and the file systems and devices that hold the data. access method In the __________ form of file structure all records are of the same length, consisting of the same number of fixed-length fields in a particular order. sequential file The essential aspects of a __________ are that the relationships that exist among elements of data are explicit and designed for use by a number of different applications database
__________ provides a general purpose record I/O capability and maintains basic data about files. Logical I/O The physical organization of the file on secondary storage depends on the blocking strategy and the __________ strategy. file allocation An objective of the __________ is to meet the data management needs and requirements of the user, which include storage of data and the ability to perform related operations. file management system The __________ is responsible for all file I/O initiation and termination. basic I/O supervisor An _________ is a control structure that contains the key information needed by the operating system for a particular file. inode (index node) Because there is no structure to the _________ form of file organization, record access is by exhaustive search. pile __________ are often used where very rapid access is required, where fixed-length records are used, and where records are always accessed one at a time. Direct files (or hashed files) The ________ is a balanced tree structure with all branches of equal length, and has become the standard method of organizing indexes for databases. B-tree Linux makes use of a __________ , which presents a single, uniform file system interface to user processes. Virtual file system Three methods of file allocation commonly used are: chained, indexed and _________ . contiguous A _________ is a collection of addressable sectors in secondary memory that an OS or application can use for data storage. volume T/F: Examples of human readable external I/O devices are printers, terminals, and keyboards True T/F: The use to which a device is put does not have an influence on the software and polices in the operating system and supporting utilities False T/F: Direct memory access is the dominant form of transfer that must be supported by the operating system. True T/F: The hierarchical philosophy is that the functions of the operating system should be separated according to their complexity, their characteristic time scale, and their level of abstraction. True T/F: The actual queuing and scheduling of I/O operations occurs at the logical I/O module False T/F: Access rights are managed at the physical organization layer. False T/F: Double buffering is when a process transfers data to (or from) one buffer while the operating system empties (or fills) the other. True T/F: RAID 0 provides real-time backups of all data so that in the event of a disk failure, all of the critical data is still immediately available. False T/F: The SCAN policy favors jobs whose requests are for tracks nearest to both innermost and outermost tracks, and favors the latest arriving jobs. True T/F: RAID is a set of physical disk drives viewed by the operating system as a single logical drive. True T/F: Windows has no way to support the encryption of entire volumes. False T/F: Cache memory reduces average memory access time by exploiting the principle of locality True T/F: A key aspect of I/O is the use of buffers that are controlled by I/O utilities rather than by application processes. True T/F: Two of the most widely used approaches to improve disk I/O performance are disk scheduling and disk cache. True T/F: In the C-SCAN disk scheduling algorithm, the disk arm is required to move in one direction only until it reaches the last track or there are no more requests to service in that direction, then it reverses direction and the scan proceeds in the opposite direction in the same fashion. False The __________ category of external devices are suitable for communicating with the computer user. A) application D
The __________ unit is capable of mimicking the processor and of taking over control of the system bus just like a processor. A) interrupt-driven I/O C __________ external devices are suitable for communicating with electronic equipment. A) Communication C The requested operations and data are converted into appropriate sequences of I/O instructions, channel commands, and controller orders at the __________ layer. A) device I/O A __________ external devices are suitable for communicating with modems. A) Human readable D __________ is a technique that smoothes out peaks in I/O demand. A) Buffering B) Blocking C) Smoothing D) Tracking A The advantage of _________ is that it provides extremely high data availability. A) RAID 2 B) RAID 4 C) RAID 0 D) RAID 6 D The _________ technique is used on a Windows server to optimize the use of threads. A) polling D On a moveable-head system, the time it takes to position the head at the track is known as ________ . A) access time B) seek time C) transfer time D) rotational delay B The advantage of __________ is that it provides extremely high data availability. A) RAID 3 B) RAID 6 C) RAID 5 D) RAID 4 B The __________ technique allows multiple simultaneous I/O requests against a single device or file. A) asynchronous procedure call B __________ are an efficient way of making consistent snapshots of volumes so that they can be backed up. A) Photo copies D RAID 5 is organized in a similar fashion to _________ , but is different in the fact that RAID 5 distributes the parity strips across all disks. A) RAID 3 B) RAID 2 C) RAID 1 D) RAID 4 D The disk scheduling algorithm that implements two sub-queues in a measure to avoid the problem of "arm stickiness" is the __________ . A) C-SCAN policy B The simplest type of support that the operating system can provide is _________ . A) overflow buffering C External devices that engage in I/O with computer systems are grouped into three categories: human readable, machine readable, and __________ . communication Disk drives, USB keys, sensors, and controllers are examples of __________ external I/O devices. machine readable A __________ module controls the exchange of data between main memory and an I/O module. direct memory access Two objectives are paramount in designing the I/O facility: generality and __________ . efficiency The __________ module deals with the device as a logical resource and is not concerned with the details of actually controlling the device logical I/O The _________ layer deals with the logical structure of files and with the operations that can be specified by users, such as open, close, read, and write. file system At the _________ layer, symbolic file names are converted to identifiers that either reference the file directly or indirectly through a file descriptor or index table. directory management The __________ policy is to select the disk I/O request that requires the least movement of the disk arm from its current position. Shortest service time first A __________ transfers data in and out as a stream of bytes, with no block structure. stream-oriented device When more than two buffers are used, the collection of buffers is itself referred to as a __________, with each individual buffer being one unit. circular buffer The sum of the seek time and the rotational delay equals the __________ , which is the time it takes to get into position to read or write. access time The simplest form of scheduling is ___________ scheduling, which processes items from the queue in sequential order. first in first out A set of logically consecutive strips that maps exactly one strip to each array member is referred to as a __________ . stripe The term _________ is usually used to apply to a memory that is smaller and faster than main memory, and that is interposed between main memory and the processor. cache memory Windows supports two sorts of RAID configurations: Software RAID and ________ . Hardware RAID A loosely coupled or distributed multiprocessor consists of a collection of relatively autonomous systems, with each processor having its own main memory and I/O channels. True With independent parallelism there is an explicit synchronization among processes. False A typical use of independent parallelism is in a time-sharing system True A disadvantage of static assignment is that one processor can be idle, with an empty queue, while another processor has a backlog. True In most traditional multiprocessor systems processes are dedicated to processors False An application can be implemented as a set of threads, which cooperate and execute concurrently in the same address space. True Because of the potential disadvantages, load sharing is not one of the commonly used schemes in current multiprocessors. False The operating system, and in particular the scheduler, is perhaps the most important component of a real-time system. True One useful measure of the ability of an operating system to function deterministically is the maximum delay from the arrival of a high-priority device interrupt to when servicing begins. True User control is generally much broader in an ordinary operating system than in a real-time operating system. False Static table-driven scheduling is applicable to tasks that are periodic. True One of the more promising methods of resolving multitask scheduling conflicts for periodic tasks is rate monotonic scheduling. True Real-time tasks are not handled any differently than non-real-time tasks in the priority queues. False Linux provided a real-time scheduling capability coupled with a scheduler for non-real-time processes that made use of the traditional UNIX scheduling algorithm True In the real-time-priority class, all threads have a fixed priority that never changes and all of the active threads at a given priority level are in a round-robin queue. True The multiprocessor system which consists of a set or processors that share a common main memory and are under the integrated control of an operating system is a _________ . tightly coupled multiprocessor With coarse and __________ grained parallelism, there is synchronization among processes, but at a very gross level. very course An example of __________ is an I/O processor. functionally specialized processors A __________ is one that must meet its deadline, otherwise it will cause unacceptable damage or a fatal error to the system. hard real-time task Typically, there will need to be a rather high degree of coordination and interaction among the threads of an application, leading to a __________ level of synchronization medium grain The __________ approach is a set of related threads scheduled to run on a set of processors at gang scheduling A _________ has an associated deadline that is desirable but not mandatory soft real-time task
With the __________ approach the number of threads in a process can be altered during the course of execution. dynamic scheduling ______ perform static analysis of feasible schedules of dispatching with the result of the analysis being a schedule that determines, at run time, when a task must begin execution. Static table-driven approaches ________ is the time required to execute the task to completion. Processing time The basic idea of _________ is that a lower-priority task inherits the priority of any higher-priority task pending on a resource they share. priority inheritance In the __________ approach, a priority is associated with each resource. priority ceiling Processes at _________ priority levels are guaranteed to be selected to run before any time-sharing process but must defer to real-time processes. kernel ____ is the lowest-priority process, intended for user applications other than real-time applications. Time-shared The __________ class is intended for applications that will only consume processor time when no other threads are ready to execute. idle user A good way of characterizing multiprocessors and placing them in context with other architectures is to consider the synchronization __________ , or frequency of synchronization between processes in a system.
granularity Linux uses _________ , in which threads are moved for a queue for one processor to a queue for another processor. dynamic load balancing In a __________ architecture, the kernel can execute on any processor, and each processor does self-scheduling from the pool of available processes. peer The _________ approach is the opposite of the load-sharing approach and provides implicit scheduling defined by the assignment of threads to processors. dedicated processor assignment _______ is useful for medium-grained to fine-grained parallel applications whose performance severely degrades when any part of the application is not running while other parts are ready to run. Gang scheduling ______ computing is defined as that type of computing in which the correctness of the system depends not only on the logical result of the computation but also on the time at which the results are produced. Real-time An _________ has a deadline by which it must finish or start, or it may have a constraint on both start and finish time. aperiodic task An operating system is __________ to the extent that it performs operations at fixed, predetermined times or within predetermined time intervals. deterministic _____ is a characteristic that refers to the ability of a system to fail in such a way as to preserve as much capability and data as possible. Fail-soft operation No feasibility analysis is performed with __________ approach, and the system tries to meet all deadlines and aborts any started process whose deadline is missed. dynamic best effort ______ is the time at which a task becomes ready for execution. Ready time For __________ scheduling, the highest-priority task is the one with the shortest period, the second highest-priority task is the one with the second shortest period, and so on. rate monotonic _____ occurs when circumstances within the system force a higher-priority task to wait for a lower-priority task. Priority inversion Processes at _________ priority levels are guaranteed to be selected to run before any kernel or time-sharing process. real time A thread is considered to be _________ if the ratio of its voluntary sleep time versus its runtime is below a certain threshold. interactive In a multiprogramming system multiple processes exist concurrently in main memory. TRUE The key to multiprogramming is scheduling. TRUE The medium-term scheduler is invoked whenever an event occurs that may lead to the blocking of the current process or that may provide an opportunity to preempt a currently running process in favor of another. FALSE Scheduling affects the performance of the system because it determines which processes will wait and which will progress. TRUE The main objective of long-term scheduling is to allocate processor time in such a way as to optimize one or more aspects of system behavior FALSE In most interactive operating systems adequate response time is the critical requirement. TRUE On problem with a pure priority scheduling scheme is that lower-priority processes may suffer starvation. TRUE First-come-first-serve (FCFS) performs much better for short processes than long ones. FALSE Round robin is particularly effective in a general purpose time sharing system or transaction processing system. TRUE The objective of a fair-share scheduler is to monitor usage to give fewer resources to users who have had more than their fair share, and more to those who have had less than their fair share. TRUE The traditional UNIX scheduler employs multilevel feedback user round robin within each of the priority queues. TRUE First-come-first-serve (FCFS) is a simple scheduling policy that tends to favor I/O bound processes over processor bound processes. FALSE In the Highest Response Ratio Next (HRRN) scheduling policy, longer jobs are favored because they yield a larger ratio from the smaller denominator in the equation. FALSE A disadvantage of simulation is that results for a given run only apply to that particular collection of processes under that particular set of assumptions. TRUE In fair share scheduling each user is assigned a weighting of some sort that defines that user's share of system resources as a fraction of the total usage of those resources. TRUE The decision as to which available process will be executed by the processor: _______________ short term scheduling The __________ determines which process, among ready processes, is selected next for execution. selection function Which scheduling policy allows the OS to interrupt the currently running process and move it to the Ready state? preemptive The __________ specifies the instants in time at which the selection function is exercised. decision mode The traditional UNIX scheduler divides processes into fixed bands of priority levels, with the highest priority band being the _________. swapper band This is a decision whether to add a new process to the set of processes that are currently active: long term scheduling A risk with __________ is the possibility of starvation for longer processes, as long as there is a steady supply of shorter processes. SPN The decision as to which process' pending I/O request shall be handled by an available I/O device: I/O scheduling In the case of the _________ policy, the scheduler always chooses the process that has the shortest expected remaining processing time. SRT (Shortest Remaining Time) This is a decision whether to add a process to those that are at least partially in main memory and therefore available for execution. medium term scheduling Response time in an interactive system is an example of: user oriented criteria for short term policies __________ considers the execution history of a related group of processes along with the individual execution history of each process in making scheduling decisions. FSS The operating system must make ________ types of scheduling decisions with respect to the execution of processes. 3 Typically, the swapping-in function for processes is based on the need to manage ___________. degree of multiprogramming The strategy that schedules processes based on their group affiliation is generally referred to as ___________. fair share scheduling The aim of ________ is to assign processes to be executed by the processor or processors over time, in a way that meets system objectives, such as response time, throughput, and processor efficiency. processor scheduling The __________ scheduler determines which programs are admitted to the system for processing. long term _________ is the elapsed time between the submission of a request until the response begins to appear as output. response time The simplest scheduling policy is __________. first come first served __________ scheduling is part of the swapping function. medium term In terms of the queuing model, _________ is the total time that the item spends in the system (waiting time plus service time). turnaround time Giving each process a slice of time before being preempted is a technique known as __________. time slicing A common technique for predicting a future value on the basis of a time series of past values is __________. exponential averaging The ___________ scheduler executes most frequently and makes the fine-grained decision of which process to execute next. short term The _________ approach means that the operating system allocates the processor to a process and when the process blocks or is preempted, feeds it back into one of several priority queues. multilevel feedback The need to know or estimate required processing times for each process, the starvation of longer processes, and the lack of preemption are all difficulties with the __________ scheduling technique. Shortest Process Next (SPN) Response time and throughput are examples of __________ criteria for short term scheduling. performance based _________ is a scheduling policy in which the process with the shortest expected processing time is select next, and if a shorter process becomes ready in the system, the currently running process is preempted. Shortest Remaining Time (SRT) The traditional UNIX scheduler, such as those used in SVR3 and 4.3 BSD UNIX systems, divides processes into fixed ________ of priority levels. bands A scheduling mechanism that requires no prior knowledge of process length, yet can nevertheless favor shorter jobs, is known as the _________ scheduling mechanism. feedback The size of virtual storage is limited by the actual number of main storage locations. FALSE The addresses a program may use to reference memory are distinguished from the addresses the memory system uses to identify physical storage sites. TRUE Most of the memory management issues confronting the operating system designer are in the are of paging when segmentation is combined with paging. TRUE Segmentation is not visible to the programmer. FALSE The placement policy determines where in real memory a process piece is to reside. TRUE
Virtual memory allows for very effective multiprogramming and relieves the user of the unnecessarily tight constraints of main memory. TRUE The principle of locality states that program and data references within a process do not tend to cluster. FALSE The smaller the page size, the greater the amount of internal fragmentation. FALSE The design issue of page size is related to the size of physical main memory and program size. TRUE Segments may be of unequal, indeed dynamic, size. TRUE The page currently stored in a frame may still be replaced even when the page is locked. FALSE One way to counter the potential performance problems of a variable-allocation global scope policy is to use page buffering. TRUE The PFF policy evaluates the working set of a process at sampling instances based on elapsed virtual time. FALSE A precleaning policy writes modified pages before their page frames are needed so that pages can be written out in batches. TRUE UNIX is intended to be machine independent; therefore its memory management scheme will vary from one system to the next. TRUE The address of a storage location in main memory is the _________. real address __________ is the virtual storage assigned to a process. virtual address space _________ is the range of memory addresses available to a process. address space The _______ structure indexes page table entries by frame number rather than by virtual page number. inverted page table The _______ states the process that owns the page. process identifier A __________ is issued if a desired page is not in main memory. page fault ___________ allows the programmer to view memory as consisting of multiple address spaces. segmentation _________ is transparent to the programmer and eliminates external fragmentation providing efficient use of main memory. paging The _________ determines when a page should be brought into main memory. fetch policy With ________ pages other than the one demanded by a page fault are brought in. prepaging The _______ policy results in the fewest number of page faults. optimal A ________ chooses only among the resident pages of the process that generated the page fault in selecting a page to replace. local replacement policy The ________ algorithm requires a use bit to be associated with each page in memory. page fault frequency ________ is where modified process pages can be written out at the time of replacement, or a precleaning policy can be used, which clusters the output activity by writing out a number of pages at once. Cleaning policy _________ is the concept associated with determining the number of processes that will be resident in main memory. Load control The address assigned to a location in virtual memory to allow that location to be accessed as though it were part of main memory is the ___________. virtual address _________ is the storage allocation scheme in which secondary memory can be addressed as though it were part of main memory. virtual memory The size of virtual storage is limited by the addressing scheme of the computer system and by the amount of ___________ available secondary memory The ______ policy treats the page frames allocated to a process as a circular buffer and pages are removed in a round robin style. FIFO The portion of a process that is actually in main memory at any time is defined to be the ____________ of the process. resident set A __________ policy allows the number of page frames allocated to a process to be varied over the lifetime of the process. variable allocation Because a process executes only in main memory, that memory is referred to as ______________. real memory When the system spends most of its time swapping pieces rather than executing instructions it leads to a condition known as ____________. thrashing To overcome the problem of doubling the memory access time, most virtual memory schemes make use of a special high-speed cache for page table entries called a ____________. translation lookaside buffer The technique where the processor is equipped with hardware that allows it to interrogate simultaneously a number of TLB entries to determine if there is a match on page number is referred to as ______________. associative mapping With _________, a page is brought into main memory only when a reference is made to a location on that page. demand paging The ___________ policy replaces the page in memory that has not been referenced for the longest time. least recently used The __________ provides a virtual memory capability that allocates page frames in main memory to processes and also allocates page frames to disk block buffers. paging system Linux makes use of a three-level page table structure consisting of the following types of tables: page directory, page table, and ___________. page middle directory In SVR4 and Solaris systems, the memory management scheme that manages memory allocation for the kernel is called the ____________. kernel memory allocator In a uniprogramming system main memory is divided into two parts. TRUE The use of unequal size partitions provides a degree of flexibility to fixed partitioning. TRUE In a multiprogramming system the available main memory is not generally shared among a number of processes. FALSE Programs in other processes should not be able to reference memory locations in a process for reading or writing purposes without permission. TRUE The memory protection requirement must be satisfied by the OS rather than the processor. FALSE Any protection mechanism must have the flexibility to allow several processes to access the same portion of main memory. TRUE Secondary memory provides fast access at relatively high cost. FALSE A hardware mechanism is needed for translating relative addresses to physical main memory addresses at the time of execution of the instruction that contains the reference. TRUE In a mulitprogramming environment the programmer knows at the time of coding how much space will be available and where that space will be. FALSE Overlay programming wastes programmer time. TRUE The principal operation of memory management is to bring processes into main memory for execution by the processor. TRUE A physical address is the location of a word relative to the beginning of the program and the processor translates that into a logical address. FALSE A best-fit algorithm is usually the worst performer. TRUE All segments of all programs must be of the same length. FALSE Segmentation does not eliminate internal fragmentation. FALSE Main memory divided into a number of static partitions at system generation time is ____________. fixed partitioning Main memory divided into a number of equal size frames is the _____________ technique. simple paging With ________ a process is loaded by loading all of its segments into dynamic partitions that need not be contiguous. simple segmentation One technique for overcoming external fragmentation is ___________. compaction A _______ is a particular example of logical address in which the address is expressed as a location relative to some known point, usually a value in a processor register. relative address The chunks of a process are known as ___________. pages Available chunks of memory are known as __________. frames The concept of Memory Management satisfies certain system requirements including: relocation, protection, and ___________. physical organization 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 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 is large enough to satisfy the request is called __________. next fit A problem with the largely obsolete Fixed Partitioning memory management technique is that of: inefficient use of memory, fixed number of processes, and ______________. internal fragmentation The page table for each process maintains _________. frame location for each page of the process In a system employing a segmentation scheme for memory management wasted space is due to _______________. external fragmentation In a system employing a paging scheme for memory management wasted space is due to ___________. internal fragmentation In a system employing a segmentation scheme for memory management a process is divided into ___________. segments which may not be of equal size The task of subdividing memory to accommodate multiple processes is carried out dynamically by the OS and is known as ___________. memory management A ___________ is a variable length block of data that resides in secondary memory. segment In a practice known as _________, the program and data are organized in such a way that various modules can be assigned the same region of memory with a main program responsible for switching the modules in and out as needed. overlaying A _______ is an actual location in main memory physical address A fixed length block of data that resides in secondary memory is a _________. page When there is wasted space internal to a partition due to the fact that the block of data loaded is smaller than the partition is referred to as ___________. internal fragmentation ______ in a computer system is organized as a linear, or one-dimensional address space, consisting of a sequence of bytes or words. main memory A ________ is a fixed length block of main memory. frame As time goes on, memory becomes more and more fragmented and memory utilization declines, creating a phenomenon referred to as __________. external fragmentation
A compromise to overcome the disadvantages of fixed partitioning and dynamic partitioning is the ___________. buddy system A _________ is a reference to a memory location independent of the current assignment of data to memory. logical address The ________ shows the frame location for each page of the process. page table A ________ can occur as a result of a programming error when a process attempts to store data beyond the limits of a fixed size buffer and consequently overwrites adjacent memory locations. buffer overflow Countermeasures to defend systems against attacks can be classified into two categories: compile-time defenses and ________. run-time defenses The basic tools of memory management are paging and ___________. segmentation. Deadlock is permanent because none of the events is ever triggered. TRUE All deadlocks involve conflicting needs for resources by two or more processes. TRUE Interrupts, signals, messages, and information in I/O buffers are all examples of reusable resources. FALSE A useful tool in characterizing the allocation of resources to processes is the resource allocation graph. TRUE
For deadlock to occur, there must not only be a fatal region, but also a sequence of resource requests that has led into the fatal region. TRUE An indirect method of deadlock prevention is to prevent the occurrence of a circular wait. FALSE If access to a resource requires mutual exclusion then mutual exclusion must be supported by the OS. TRUE The OS may preempt the second process and require it to release its resources if a process requests a resource that is currently held by another process. TRUE Deadlock avoidance requires knowledge of future process resource requests. TRUE An unsafe state is one in which there is at least one sequence of resource allocations to processes that does not result in a deadlock. FALSE An atomic operation executes without interruption and without interference. TRUE Deadlock avoidance is more restrictive than deadlock prevention. FALSE The dining philosopher's problem can be representative of problems dealing with the coordination of shared resources which may occur when an application includes concurrent threads of execution. TRUE A signal is similar to a hardware interrupt but does not employ priorities. TRUE A mutex is used to ensure that only one thread at a time can access the resource protected by the mutex. TRUE A set of processes is _________ when each process in the set is blocked awaiting an event that can only be triggered by another blocked process in the set. deadlocked Examples of _______ include processors, I/O channels, main and secondary memory, devices, and data structures such as files, databases, and semaphores. reusable resources With _______ only one process may use a resource at a time and no process may access a resource unit that has been allocated to another process. mutual exclusion A closed chain of processes exists, such that each process holds at least one resource needed by the next process in the chain is the condition of __________. circular wait Once the processes have progressed into the _________, those processes will deadlock. fatal region The strategy of deadlock __________ is to design a system in such a way that the possibility of deadlock is excluded. prevention The __________ condition can be prevented by requiring that a process request all of its required resources at one time and blocking the process until all requests can be granted simultaneously. hold and wait The fastest form of interprocess communication provided in UNIX is _____________. shared memory The ____________ condition can be prevented by defining a linear ordering of resource types. circular wait Requested resources are granted to processes whenever possible with ____________. deadlock detection One of the most significant contributions of UNIX to the development of operating systems is the ___________. pipe A _________ is a software mechanism that informs a process of the occurrence of asynchronous events. signal The most common technique used for protecting a critical section in Linux is the ____________. spinlock The __________ allows multiple threads to have simultaneous read-only access to an object protected by the lock. readers/writer lock The ___________ is useful in sending a signal to a thread indicating that a particular event has occurred. event object _________ can be defined as the permanent blocking of a set of processes that either compete for system resources or communicate with each other. deadlock A ______ resource is one that can be safely used by only one process at a time and is not depleted by that use. reusable A ________ resource is one that can be created and destroyed. consumable The ________ is a directed graph that depicts a state of the system of resources and processes, with each process and each resource represented by a node. resource allocation graph Three conditions of policy must be present for a deadlock to be possible: mutual exclusion, no preemption, and ________. hold and wait Three general approaches exist for dealing with deadlock: prevent, avoid, and ______. detect _________ allows the three necessary conditions but makes judicious choices to assure that the deadlock point is never reached. avoidance
The strategy of resource allocation denial is referred to as the ___________. banker's algorithm The ________ of the system reflects the current allocation of resources to processes. state ________ strategies are very conservative and solve the problem of deadlock by limiting access to resources and by imposing restrictions on processes. prevention Inspired by the concept of co-routines, a ________ is a circular buffer allowing two processes to communicate on the producer-consumer model. pipe Two types of atomic operations are defined in Linux: integer operations and _______________. bitmap operations Linux provides three types of semaphore facilities in the kernel: binary semaphores, counting semaphores, and ________. reader-writer semaphores an executable entity within a process is a _________ object. thread A program invocation, including the address space and resources required to run the program is a ______ object. process The central themes of operating system design are all concerned with the management of processes and threads. TRUE It is possible in a single-processor system to not only interleave the execution of multiple processes but also overlap them FALSE As an extension of the principles of modular design and structured programming, some applications can be effectively programmed as a set of concurrent processes. TRUE Race condition is a situation in which two or more processes continuously change their states in response to changes in the other process(es) without doing any useful work. FALSE The sharing of main memory among processes is useful to permit efficient and close interaction among processes because such sharing does not leads to many problems. FALSE When processes cooperate by communication, the various processes participate in a common effort that links all of the processes. TRUE Atomicity guarantees isolation from concurrent processes. TRUE Concurrent processes do not come into conflict with each other when they are competing for the use of the same resource. FALSE Two or more processes can cooperate by means of simple signals, such that a process can be forced to stop at a specified place until it has received a specific signal. TRUE The functioning of a process, and the output it produces, must be independent of the speed at which its execution is carried out relative to the speed of other concurrent processes. TRUE A process that is waiting for access to a critical section does not consume processor time. FALSE The case of cooperation by sharing covers processes that interact with other processes without being explicitly aware of them. TRUE It is possible for one process to lock the mutex and for another process to unlock it. FALSE On of the most common problems faced in concurrent processing is the producer/consumer problem. TRUE Processes need to be synchronized to enforce mutual exclusion. TRUE The management of multiple processes within a uniprocessor system is ___________. multiprogramming A situation in which a runnable process is overlooked indefinitely by the scheduler, although it is able to proceed, is ____________. starvation The requirement that when one process is in a critical section that access shared resources, no other process may be in a critical section that accesses any of those shared resources is ____________. mutual exclusion A means for two processes to exchange information is with the use of ____________. messages A semaphore that does not specify the order in which processes are removed from the queue is a _________ semaphore. weak A ____________ occurs when multiple processes or threads read and write data items so that the final result depends on the order of execution of instructions in the multiple processes. race condition A ___________ is an integer value used for signaling among processes. semaphore __________ is when the sequence of instruction is guaranteed to execute as a group, or not execute at all, having no visible effect on system state. atomic operation ___________ are memory words used as a synchronization mechanism. event flags The term _________ refers to a technique in which a process can do nothing until it gets permission to enter its critical section but continues to execute an instruction or set of instructions that tests the appropriate variable to gain entrance. spin waiting A _______ is a data type that is used to block a process or thread until a particular condition is true. condition variable A semaphore whose definition includes the policy that the process that has been blocked the longest is released from the queue first is called a __________ semaphore. strong The __________ is a programming language construct that provides equivalent functionality to that of semaphores and is easier to control. monitor Probably the most useful combination, ________ allows a process to send one or more messages to a variety of destinations as quickly as possible. nonblocking send, blocking receive A ___________ relationship allows multiple server processes to provide concurrent service to multiple clients. many-to-many ____________ arises in three different contexts: multiple applications, structured application, and operating system structure. concurrency _________ was invented to allow processing time to be dynamically shared among a number of active applications. multiprogramming A situation in which two or more processes are unable to proceed because each is waiting for one of the others to do something is a ____________. deadlock In the case of competing processes three control problems must be faced: mutual exclusion, deadlock, and _________. starvation A ______________ is a semaphore that takes only the values of 0 and 1. binary semaphore A situation in which multiple threads or processes read and write a shared data item and the final result depends on the relative timing of their execution is a ___________ . race condition __________ is a function or action implemented as a sequence of one or more instructions that appears to be indivisible; no other process can see an intermediate state or interrupt the operations. atomic operation A ___________ is a programming language construct that encapsulates variables, access procedures, and initialization code within an abstract data type. monitor __________ is a section of code within a process that requires access to shared resources and that must not be executed while another process is in a corresponding section of code. critical section In the case of _________, processes are sharing resources without being aware of the other processes. competition A __________ is a mutual exclusion mechanism in which a process executes in an infinite loop waiting for the value of a lock variable to indicate availability spinlock Only three operations may be performed on a semaphore: initialize, increment, and __________. decrement A monitor supports synchronization by the use of _________ that are contained within the monitor and accessible only within the monitor. condition variables In the case of _______, messages are not sent directly from sender to receiver but rather are sent to a shared data structure consisting of queues that can temporarily hold messages. indirect addressing The classic concurrency problem that involves multiple readers that can read from a shared data area when no single writer is exclusively writing to it is the ___________ Problem. readers/writers The OS performs a protection function to prevent unwanted interference between processes with respect to resources. TRUE Windows process design is driven by the need to provide support for a variety of OS environments. TRUE The unit of dispatching is usually referred to as a process or task. FALSE
In a multithreaded environment there are separate stacks for each thread, as well as a separate control block for each thread. TRUE It takes less time to terminate a process than a thread. FALSE If there is an application or function that should be implemented as a set of related units of execution, it is far more efficient to do so as a collection of separate processes rather than a collection of threads. FALSE An example of an application that could make use of threads is a file server. TRUE Termination of a process does not terminate all threads within that process. FALSE If a process is swapped out, all of its threads are necessarily swapped out because they all share the address space of the process. TRUE On a uniprocessor, multiprogramming does not enable the interleaving of multiple threads within multiple processes. FALSE Any alteration of a resource by one thread affects the environment of the other threads in the same process. TRUE In a pure ULT facility, all of the work of thread management is done by the application, and the kernel is not aware of the existence of threads. TRUE As a default, the kernel dispatcher uses the policy of hard affinity in assigning threads to processors. FALSE Windows is an example of a kernel-level thread approach. TRUE The potential performance benefits of a multicore organization depend on the ability to effectively exploit the parallel resources available to the application. TRUE The traditional approach of a single thread of execution per process, in which the concept of a thread is not recognized, is referred to as a ______________. single-threaded approach The idea of having a many-to-many relationship between threads and processes has been explored in the experimental operating system ___________. TRIX In a multithreaded environment, a _________ is defined as the unit of resource allocation and a unit of protection. process The principal disadvantage of the _______ approach is that the transfer of control from one thread to another within the same process requires a mode switch to the kernel. kernel-level thread _________ is a good example of an OS using a combined user-level and kernel-level thread approach. Solaris A _______ is a single execution path with an execution stack, processor state, and scheduling information. thread _________ are characterized by the presence of many single-threaded processes. multiprocess applications A _______ is a dispatchable unit of work that executes sequentially and is interruptible so that the processor can turn to another thread. thread A _________ is an entity corresponding to a user job or application that owns resources such as memory and open files. process A ________ is a user-created unit of execution within a process. user-level thread A windows process must contain at least ________ thread(s) to execute. 1 A thread enters the ________ state, after waiting, if it is ready to run but the resources are not available. transition The _________ are the fundamental entities that can be scheduled and dispatched to run on one of the system processors. Kernel threads The _______ state is when the thread has terminated. ZOMBIE The blocked state in which the process is waiting for an event, such as the end of an I/O operation, the availability of a resource, or a signal from another process is the __________ state. interruptible The _______ is the collection of program, data, stack, and attributes defined in the process control block. process image ________ refers to the ability of an OS to support multiple, concurrent paths of execution within a single process. Multithreading The key states for a thread are: Running, ________, and Blocked. Ready There are four basic thread operations associated with a change in thread state: Block, Unblock, Finish, and ________. Spawn There are two broad categories of thread implementation: user-level threads and ____________. kernel-level threads A way to overcome the problem of blocking threads is to use a technology referred to as __________, which converts a blocking system call into a nonblocking system call. jacketing A __________ is a static entity, consisting of an address space and ports through which messages may be sent and received. domain Windows makes use of two types of process-related objects: processes and __________. threads The _________ Windows Process Object Attribute describes who created an object, who can gain access to or use the object, and who is denied access to the object. security descriptor The six states of a Windows thread are: Ready, Standby, Running, Waiting, Transition, and ___________. Terminated Most operating systems contain two fundamental forms of concurrent activity: processes and ____________. interrupts
A process or task in Linux is represented by a ___________ data structure. task_struct The Clouds operating system implements the concept of a thread as primarily an entity that can move among address spaces which represents the ___________ Thread-to-Process relationship. One-to-Many It is necessary to ___________ the activities of various threads so they do not interfere with each other or corrupt data structures. synchronize The basic form of communication between processes or threads in a micro kernel operating system is ___________. messages A computer platform consists of a collection of hardware resources, such as the processor, main memory, I/O modules, timers, and disk drives. TRUE For efficiency, applications should be written directly for a given hardware platform. FALSE A design change in the structure or semantics of the process control block could affect a number of modules in the OS. TRUE The process control block is the key tool that enables the OS to support multiple processes and to provide for multiprocessing. TRUE It is not the responsibility of the operating system to control the execution of processes. FALSE The first step in designing an OS to control processes is to describe the behavior that we would like the processes to exhibit. TRUE The OS may create a process on behalf of an application. TRUE Swapping is not an I/O operation so it will not enhance performance. FALSE If a system does not employ virtual memory each process to be executed must be fully loaded into main memory. TRUE A process that is not in main memory is immediately available for execution, regardless of whether or not it is awaiting an event. FALSE The OS may suspend a process if it detects or suspects a problem. TRUE All processor designs include a register or set of registers, often known as the program status word, which contains status information. TRUE The process control block is the least important data structure in an OS. FALSE A process switch may occur any time that the OS has gained control from the currently running process. TRUE The principal function of the OS is to create, manage, and terminate processes. TRUE The processor itself provides only limited support for multiprogramming, and _______ is needed to manage the sharing of the processor and other resources by multiple applications at the same time. software "The process was placed in a suspended state by an agent; either itself, a parent process, or the OS, for the purpose of preventing its execution," is a characteristic of a ______ process. suspended A _______ is a unit of activity characterized by the execution of a sequence of instructions, a current state, and an associated set of system resources. process We can characterize the behavior of an individual process by listing the sequence of instructions, referred to as a _______, that executes for that process. trace It is the principal responsibility of the _________ to control the execution of processes. OS When one process spawns another, the spawned process is referred to as the ______________. child process _________ involves moving part or all of a process from main memory to disk. Swapping When a process is in the ________ state it is in secondary memory but is available for execution as soon as it is loaded into main memory. Ready/Suspended A process is in the ______ state when it is in main memory and awaiting an event. Blocked The OS must maintain _________ tables to manage processes. process The collection of program, data, stack, and attributes is referred to as the _________. process image The _________ is the less-privileged mode. user mode A ________ is an individual who seizes supervisory control of the system and uses this control to evade auditing and access controls or to suppress audit collection. clandestine user A total of _________ process states are recognized by the UNIX SVR4 operating system. 9 The portion of the OS that selects the next process to run is called the ___________, dispatcher The ________ is a layer of software between the applications and the computer hardware that supports applications and utilities. OS A process is in the ________ state when it is in secondary memory and awaiting an event. Blocked/Suspended Two essential elements of a process are ________ and a set of data associated with that code. program code The _________ tables provide information about the existence of files, their location on secondary memory, their current status, and other attributes. file A significant point about the ________ is that it contains sufficient information so that it is possible to interrupt a running process and later resume execution as if the interruption had not occurred. process control block A _________ is a legitimate user who accesses data, programs, or resources for which such access is not authorized, or who is authorized for such access but misuses their privileges. misfeasor When the OS creates a process at the explicit request of another process, the action is referred to as _________. process spawning The process is said to be operating in a _________ fashion if each process in the queue is given a certain amount of time, in turn, to execute and then returned to the queue, unless blocked. round robin A process in the _______ state is in main memory and available for execution. Ready
________ tables are used to keep track of both main (real) and secondary (virtual) memory. Memory The process control block information can be grouped into three general categories: Process identification, ________, and process control information. processor state information A ________ is the maximum amount of time that a process can execute before being interrupted. Time slice System access threats fall into two general categories: _________ and malicious software. intruders a _______ is an individual who is not authorized to use the computer and who penetrates a system's access controls to exploit a legitimate user's account. masquerader An IDS comprises three logical components: sensors, ________, and user interface. analyzers An OS should be constructed in such a way as to permit the effective development, testing, and introduction of new system functions without interfering with service. TRUE The OS masks the details of the hardware from the programmer and provides the programmer with a convenient interface for using the system. TRUE The ABI gives a program access to the hardware resources and services available in the system through the user ISA. FALSE The OS frequently relinquishes control and must depend on the processor to allow it to regain control. TRUE On of the driving forces in operating system evolution is advancement in the underlying hardware technology. TRUE The processor itself is not a resource so the OS is not involved in determining how much of the processor time is devoted to the execution of a user program. FALSE A process consists of three components: an executable program, the associated data needed by the program, and the execution context of the program. TRUE Uniprogramming typically provides better utilization of system resources than multiprogramming. FALSE A monolithic kernel is implemented as a single process with all elements sharing the same address space. TRUE The user has direct access to the processor with batch-processing type OS. FALSE Both batch processing and time sharing use multiprogramming. TRUE The phrase "control is passed to a job" means that the processor is now fetching and executing instructions from the monitor program. FALSE In a time sharing system, a user's program is preempted at regular intervals, but due to the relatively slow human reaction time this occurrence is usually transparent to the user. TRUE The principle objective of Batch Multiprogramming is to minimize response time. FALSE Virtualization technology enables a single PC or server to simultaneously run multiple operating systems or multiple sessions of a single OS. TRUE The _________ interface is the interface that is the boundary between hardware and software. ISA A(n) __________ is a set of resources for the movement, storage, and processing of data and for the control of these functions. computer The operating system's ________ refers to its inherent flexibility in permitting functional modifications to the system without interfering with service. ability to evolve Operating systems must evolve over time because: new hardware is designed and implemented in the computer system A special type of programming language used to provide instructions to the monitor is __________. JCL Hardware features desirable in a batch-processing operating system include memory protection, timer, privileged instructions, and ____________. interrupts A user program executes in a __________, in which certain areas of memory are protected for the user's use and in which certain instructions may not be executed. user mode Multiprogramming operating systems are fairly sophisticated compared to single-program or __________ operating systems. uniprogramming One of the first time-sharing operating systems to be developed was the ______________. Compatible Time-Sharing System The technique where a system clock generates interrupts, and at each clock interrupt the OS regains control and assigns the processor to another user, is called ________. time slicing The _________ is the internal data by which the OS is able to supervise and control the process. execution context ________ is where the OS must prevent independent processes from interfering with each other's memory, both data and instructions. Process isolation __________ is concerned with the proper verification of the identity of users and the validity of messages or data. Authenticity A common strategy to give each process in the queue some time in turn is referred to as a ___________ technique. round robin The key to the success of Linux has been its character as a free software package available under the auspice of the ____________. Free Software Foundation An _________ is a program that controls the execution of application programs and acts as an interface between applications and the computer hardware. operating system The portion of the monitor that is always in main memory and available for execution is referred to as the _____________. resident monitor __________ is a technique in which a process, executing an application, is divided into threads that can run concurrently. Multithreading Two major problems with early serial processing systems were scheduling and ____________. setup time The central idea behind the simple batch-processing scheme is the use of a piece of software known as the _________. monitor Any resource allocation and scheduling policy must consider three factors: Fairness, Differential responsiveness, and ________. efficiency A_______ is set at the beginning of each job to prevent any single job from monopolizing the system. timer The OS has five principal storage management responsibilities: process isolation, automatic allocation and management, support of modular programming, protection and access control, and ________ long-term storage. The earliest computers employed _________ processing, a name derived by the way the users have access to the systems. Serial ___________ was designed to keep the processor and I/O devices, including storage devices, simultaneously busy to achieve maximum efficiency. Multiprogramming In a time-sharing, multiprogramming system, multiple users simultaneously access the system through _________. terminals The principal objective of __________ is to maximize processor use. Batch Multiprogramming 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 operations, time sharing, and ________. real-time transaction systems ______________ is a facility that allows programs to address memory from a logical point of view, without regard to the amount of main memory physically available. Virtual memory Security and protections as it relates to operating systems is grouped into four categories: Availability, Data integrity, Authenticity, and __________. Confidentiality The processor controls the operation of the computer and performs its data processing functions TRUE It is possible for a communications interrupt to occur while a printer interrupt is being processed. TRUE A system bus does not transfer data between the computer and its external environment. TRUE Cache memory is invisible to the OS. TRUE With interrupts, the processor can not be engaged in executing other instructions while an I/O operation is in progress. FALSE Digital Signal Processors deal with streaming signals such as audio and video. TRUE The fetched instruction is loaded into the Program Counter. FALSE
Interrupts are provided primarily as a way to improve processor utilization. TRUE The interrupt can occur at any time and therefore at any point in the execution of a user program. TRUE Over the years memory access speed has consistently increased more rapidly than processor speed. FALSE An SMP can be defined as a stand-alone computer system with two or more similar processors of comparable capacity. TRUE The Program Status Word contains status information in the form of condition codes, which are bits typically set by the programmer as a result of program operation. FALSE An example of a multicore system is the Intel Core i7. TRUE In a two-level memory hierarchy the Hit Ratio is defined as the fraction of all memory accesses found in the slower memory. FALSE The operating system acts as an interface between the computer hardware and the human user. TRUE The four main structural elements of a computer system are: Processor, Main Memory, I/O Modules and System Bus The ___________ holds the address of the next instruction to be fetched. Program Counter The ___________ contains the data to be written into memory and receives the data read from memory. memory buffer register Instruction processing consists of two steps: fetch and execute The ___________ routine determines the nature of the interrupt and performs whatever actions are needed. interrupt handler The unit of data exchanged between cache and main memory is __________. block size The _________ chooses which block to replace when a new block is to be loaded into the cache and the cache already has all slots filled with other blocks. replacement algorithm __________ is more efficient than interrupt-driven or programmed I/O for a multiple-word I/O transfer. Direct memory access The _________ is a point-to-point link electrical interconnect specification that enables high-speed communications among connected processor chips. QPI Small, fast memory located between the processor and main memory is called: Cache memory In a uniprocessor system, multiprogramming increases processor efficiency by: Taking advantage of time wasted by long wait interrupt handling The two basic types of processor registers are: User-visible and Control/Status When an external device becomes ready to be serviced by the processor the device sends a(n) __________ signal to the processor. interrupt One mechanism Intel uses to make its caches more effective is ________, in which the hardware examines memory access patterns and attempts to fill the caches speculatively with data that is likely to be requested soon. prefetching A __________ organization has a number of potential advantages over a uniprocessor organization including performance, availability, incremental growth, and scaling. symmetric multiprocessor The invention of the ________ was the hardware revolution that brought about desktop and handheld computing. microprocessor To satisfy the requirements of handheld devices, the classic microprocessor is giving way to the ________, where not just the CPUs and caches are on the same chip, but also many of the other components of the system, such as DSPs, GPUs, I/O devices and main memory. System on a Chip (SoC) The processing required for a single instruction is called a(n) _________ cycle. instruction The fetched instruction is loaded into the _________. Instruction Register (IR) When an external device is ready to acept more data from the processor, the I/O module for that external device sends an ____________ signal to the processor. interrupt request The ___________ is a device for staging the movement of data between main memory and processor registers to improve performance and is not usually visible to the programmer or processor. cache External, nonvolatile memory is also referred to as _________ or auxiliary memory. secondary memory When a new block of data is read into the cache the ____________ determines which cache location the block will occupy. mapping function In a _______ multiprocessor all processors can perform the same functions so the failure of a single processor does not halt the machine. symmetric A __________ computer combines two or more processors on a single piece of silicon. multicore A Control/Status register that contains the address of the next instruction to be fetched is called the ____________. Program Counter (PC) Each location in Main Memory contains a _________ value that can be interpreted as either and instruction or data. binary number A special type of address register required by a system that implements user visible stack addressing is called a ______. stack pointer. Registers that are used by system programs to minimize main memory references by optimizing register use are called ________. user-visible registers The concept of multiple programs taking turns in execution is known as ___________. multiprogramming Recommended textbook solutions
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Can a server be both client and server?There are many types of servers, including web servers, mail servers, and virtual servers. An individual system can provide resources and use them from another system at the same time. This means that a device could be both a server and a client at the same time.
What is true about a clientWhat is true about a client-server network? In a client-server network, a dedicated server responds to service requests from clients. The roles of client and server are not shared on each host in the network. In a peer-to-peer network, computers are connected via a network and can share resources.
Can a client be a server at the same time?Yes, a process can host any number (within reason) of server and/or client instances simultaneously.
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In a client-server system, the client and the server always run on different machines true false
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