operating system principles seventh edition pdf

... also provide a good platform for operating system research since many differentoperating systems may run on one physical system Trang 1812 Chapter 3 Operating-System Structures3.14 Why is a just-in-time ... modern operating systems A process is is a program in execution and is the unit of work in a modern time-sharing system Such a system consists of a collection of processes: Operating-system processes ... uniprocessorsystems 1.10 What is the main difficulty that a programmer must overcome in writing an operatingsystem for a real-time environment? con-straints of a real-time system If the system does

Ngày tải lên: 28/06/2014, 00:20

... [...]... operating systems (for example, [29, 11 , 26] to cite but three from the past twenty years) The classical operating system kernel is to be found in most of the systems today: ... IBM’s mainframe operating systems and many real-time kernels In days of greater diversity, it was the approach adopted in the design of Digital Equipment’s operating systems: RSTS, RSX ... Operating systems are, arguably, the most critical part of any computer system The kernel manages the computational resources used by applications Recent episodes have shown that the operating

Ngày tải lên: 23/07/2014, 23:20

... LESSON 9 Linux Operating System Vulnerabilities and security Objectives ♦ Describe the fundamentals of the Linux operating system ♦ Describe the vulnerabilities of the Linux operating system ♦ Describe ... system ♦ Describe Linux remote attacks ♦ Explain countermeasures for protecting the Linux operating system 2 Review of Linux Security Fundamentals ♦ Linux is a version of UNIX – Usually available ... sc/etc/shadow Root:2bcadvr345:0:0:root: /root: /bin/bash - John The Ripper - Viper - Slurple 6 7 Linux File System ♦ Ls –l ♦ -r-x-r-x-wx ♦ Chmod 777 a.txt Firewall: iptables 8 9 10

Ngày tải lên: 29/07/2014, 08:20

... Chapter 2 Operating-System Structures 2.1 Operating-System Services 39 2.7 Operating-System Structure 582.2 User Operating-System Interface 41 2.8 Virtual Machines 64 2.3 System Calls 43 2.9 Operating-System ... a few otherinfluential operating systems Operating-System Environments This book uses examples of many real-world operating systems to illustratefundamental operating-system concepts However, ... What Operating Systems Do 3 1.9 Protection and Security 26 1.2 Computer-System Organization 6 1.10 Distributed Systems 28 1.3 Computer-System Architecture 12 1.11 Special-Purpose Systems 29 1.4 Operating-System

Ngày tải lên: 12/08/2014, 22:21

... Host Operating System The JVM is typically implemented on top of a host operating system (see Pigure 2.17). This setup allows the JVM to bide the implementation details of the underlying operating ... the host operating system. For example, implementations of a. JVM for the Windows family of operating systems might use the Win32 API when creating Java threads; Linux and Solaris systems might ... be mapped to the underlying operating system, instead leaving that decision to the particular implementation.of the JVM. For example, the Windows XP operating system uses the one-to-one

Ngày tải lên: 12/08/2014, 22:21

... simplest case is the single-user system Consider a single-user systemwith 128 KB of memory composed of pages 1 KB in size This system has 128frames The operating system may take 35 KB, leaving ... Replacement In certain cases, applications accessing data through the operating system'svirtual memory perform, worse than if the operating system provided nobuffering at all A typical example is a database, ... understandtheir memory use and disk use better than does an operating system that isimplementing algorithms for general-purpose use If the operating system isbuffering I/O, and the application is doing

Ngày tải lên: 12/08/2014, 22:21

... forhow to boot a specific operating system For instance, PCs and other systemscan be dual-booted Multiple operating systems can be installed, on such asystem How does the system know which one to ... containing a differenttype of file system and a different operating system The root partition, which contains the operating-system kernel and some-times other system files, is mounted at boot ... the operating system notes in its in-memory mount table structure that a file system is mounted, along with the type of the file system The details of this function depend on the operating system

Ngày tải lên: 12/08/2014, 22:21

... do it through the operating system To do I/O, a user programexecutes a system call to request that the operating system perform I/O on itsbehalf (Figure 13.11) The operating system, executing ... is no longer needed Other operating systems enforce a limit of oneopen file handle to such a device Many operating systems provide functions Trang 513.4 Kernel I/O Subsystem 515that enable processes ... protection system is generally more complex and less efficientthan are those used in current operating systems If protection interferes withthe ease of use of the system or significantly decreases system

Ngày tải lên: 12/08/2014, 22:21

... Distributed Operating Systems In this section, we describe the two general categories of network-orientedoperating systems: network operating systems and distributed operatingsystems Network operating systems ... users to access and utilize than are distributed operatingsystems, which provide more features 16.2.1 Network Operating Systems A network operating system provides an environment in which users, ... adifferent set of commands Distributed operating systems are designed toaddress this problem 16.2.2 Distributed Operating Systems In a distributed operating system, the users access remote resources

Ngày tải lên: 12/08/2014, 22:21

... UNIX system This gives a student of operating systems an opportunity to read—and modify— real operating-system source code. We also cover Windows XP in great detail This recent operatingsystem ... Linux operating system with a small real-time ker-nel, thereby providing a system that acts as both a general-purpose and a real-time system This is the approach taken by the RTLinux operatingsystem ... real-time systems, we distinguished between soft real-time systems and hard real-time systems Soft real-time systems simply give scheduling priority to critical processes A soft real-time systemensures

Ngày tải lên: 12/08/2014, 22:21

... implement particular operating-system personalities The client-server model is used for implementing a variety of operating-system services besides the environmental subsystems Security management, ... in the system. The lower 2 GB are specific to each process and are accessible by both user- and kernel-mode threads. Certain configurations of Windows XP reserve only 1 GB for operating-system ... name space. In contrast to UNIX, which roots the system name space in the file system, Windows XP uses an abstract name space and connects the file systems as devices. The object manager provides

Ngày tải lên: 12/08/2014, 22:21

... versions of Window's operating Systems hay ised preemptive scheduling The Mac OS * operating system for the M also uses preemptive scheduling, previous ns of the Macintosh ones 3 system relied on ... introduced threads to the process model O i systems that support them, it is kernel-level threads nel roce 2 eee in fact being scheduled by the operating system ae the oS a ee scheduling and thread ... Trang 1cpu scheduling is the basis o i Be aching the CPU among The operating systems By computer more Brodtictive.In oe độc nã —— system can make the concepts and present several ee ie NHAN „

Ngày tải lên: 29/04/2017, 10:18

... memory All of the processes in main memory are blocked, and OS brings in Process D 35 Paging • Operating system maintains a page table for each process which contains the frame location for each page ... to the same copy of the program rather than have their own separate copy – Processes that are cooperating on some task may need to share access to the same data structure Logical Organization

Ngày tải lên: 30/01/2020, 00:31

... scheduling is to assign processes to be executed by the processor over time, – in a way that meets system objectives, such as response time, throughput, and processor efficiency Scheduling Objectives ... and to optimize performance Long-Term Scheduling • Determines which programs are admitted to the system for processing – May be first-come-first-served – According to criteria such as priority,

Ngày tải lên: 30/01/2020, 00:39

... Allocation Denial• Referred to as the banker’s algorithm • Consider a system with fixed number of resources – State of the system is the current allocation of resources to process. – Safe state ... is received). Trang 14Resource Allocation Graphs • Directed graph that depicts a state of the system of resources and processes an instance of a resource Trang 16Actual Deadlock Requires … ... conditions 1 through 4 hold and take action to recover Trang 21Deadlock Prevention Strategy • Design a system in such a way that the possibility of deadlock is excluded • Two main methods – Indirect:

Ngày tải lên: 30/01/2020, 01:28

... interleaved with other processes • These two characteristics are treated independently by the operating system Trang 3Processes and Threads• The unit of dispatching is referred to as a thread or ... process share this) Trang 9One view…• One way to view a thread is as an independent program counter operating within a process. Trang 10Threads vs processes Trang 11Threads vs processes• The thread

Ngày tải lên: 30/01/2020, 02:33

... Chapter and Computer System and Operating System Overview – The Evolution of Operating Systems – OS Objectives and Functions – Instruction Execution – ... Evolution of Operating Systems • It may be easier to understand the key requirements of an OS by considering the evolution of Operating Systems • Stages include – Serial Processing – Simple Batch Systems ... Processing – Simple Batch Systems – Multiprogrammed Batch Systems – Time Sharing Systems Serial Processing (late 1940s to mid-1950s) • No operating system • Machines run from a console with display lights,

Ngày tải lên: 30/01/2020, 02:42

... critical and – data are rarely processed exhaustively – examples: airline reservation systems and inventory control systems Trang 21Directory Elements• Basic Information – File name: must be unique ... PictureHow to identify and locate a selected file? How to enforce user access control in shared systems? How to organize records as a sequence of blocks for I/O? individual block I/O requests ... the working directory unless an explicit full pathname is used Trang 28File Sharing• In multiuser system, there is almost always a requirement for allowing files to be shared among a number of

Ngày tải lên: 30/01/2020, 05:07

... Trang 1Chapter 11 I/O Management and Disk Scheduling– Operating System Design Issues – I/O Buffering – Disk Scheduling – Disk Cache Trang 2• Solution: use ... 14Single Buffer• OS assigns a buffer in the system portion of main memory for an I/O request Trang 15Block Oriented Single Buffer• Input transfers are made to system buffer • Block moved to user space ... I/O operation is taking place in system memory Trang 17Block Oriented Single Buffer•  Complicate the logic in OS – OS must keep track of the assignment of system buffers to user processes •

Ngày tải lên: 30/01/2020, 05:13