operating system book by galvin ppt

... threecolor components), and because it is a color system with which many program-mers and end users are familiar with (it’s common to several operating systems).The BeOS defines rgb_color as a struct ... bits) in an 8-pixel-by-8-pixelarea display the current high color and which display the current low color Thusthe specific colors displayed by the pattern aren’t designated by the pattern.Instead, ... bits aren’t ignored—they’re devoted to defining analpha byte, which is used to specify a transparency level for a color Trang 3RGB Color SystemAs listed above, the BeOS supports a number of color

Ngày tải lên: 26/01/2014, 07:20

... phosphorylation was blocked by an Src kinaseinhibitor or by small interfering RNAs directed against Fynand Fgr and was enhanced by overexpression of Fyn and Fgrbut not by other Src kinases The phosphorylation ... to milk glycans, followed by those of seminal fluids and salivas, while UEA-I was only inhibited by ‘‘secretor’’ body fluids, most strongly by seminal fluids, followed by milks and salivas Conclusions: ... induced by the downregula-tion of Nat5 expression is induced by the activadownregula-tion of p53 that induces an increase of p21 mRNA and protein presents in the cell V1-004P Plants as alternative systems

Ngày tải lên: 30/03/2014, 20:20

... denotes the queue of highest-priority processes System processes must be preferred by the scheduler to user processes but should be pre-empted by device processes, so sysprocqueue denotes the ... process is represented by currentp The time tum of the current process is represented by currentquant (if it is a user-level process) For all processes, the priority is represented by currentplev quan-The ... the table This is done in this model by manipulating a set of identifiers, asfollows When an identifier is in this set, it is considered available for use by Trang 3116 4 A Swapping Kernela new

Ngày tải lên: 23/07/2014, 23:20

... number of megabytes assigned to Slice For example, if the disk reports 8.4 Gbytes, record 8600 Mbytes (8.4 x 1024, rounded to the nearest 10 Mbytes) Mbytes: Divide the number of megabytes by Use the ... input to the system This level also includes the task solutions for all three levels Intermediate System Administration for the Solaris™ 10 Operating System Copyright 2005 Sun Microsystems, Inc ... the disk by typing label partition> label Ready to label disk, continue? y partition> 3-44 Intermediate System Administration for the Solaris™ 10 Operating System Copyright 2005 Sun Microsystems,

Ngày tải lên: 12/08/2014, 22:21

... pane to display the systemmanagement tools Trang 8Managing User Accounts10-28 Intermediate System Administration for the Solaris™ 10 Operating System Copyright 2005 Sun Microsystems, Inc All Rights ... System Administration for the Solaris™ 10 Operating System Copyright 2005 Sun Microsystems, Inc All Rights Reserved Sun Services, Revision A.1 4 Click User Accounts, and add theuser5account by ... Intermediate System Administration for the Solaris™ 10 Operating System Copyright 2005 Sun Microsystems, Inc All Rights Reserved Sun Services, Revision A.1 3 Launch the Solaris Management Console by typing

Ngày tải lên: 12/08/2014, 22:21

... main-memory references by optimizing register use • Control and status registers – Used by processor to control operating of the processor – Used by privileged operating-system routines to control ... Trang 1Computer System Overview Chapter 1 Trang 2Operating System• Exploits the hardware resources of one or more processors • Provides a set of services to system users • Manages secondary ... programs Trang 7User-Visible Registers • May be referenced by machine language • Available to all programs - application programs and system programs • Types of registers – Data – Address • Index

Ngày tải lên: 09/01/2018, 12:01

... Executive • Polymorphism Trang 63UNIX • Hardware is surrounded by the operating system software • Operating system is called the system kernel • Comes with a number of user services and interfaces ... Distributed operating systems – Provides the illusion of a single main memory space and single secondary memory space Trang 52– Enables programmers to customize an operating system without disrupting system ... application written for other operating system Trang 5454Trang 55Operating System Organization • Modified microkernel architecture – Not a pure microkernel – Many system functions outside of the

Ngày tải lên: 09/01/2018, 12:01

... Trang 5353Trang 5454Trang 55Execution of the Operating System • Process-Based Operating System – Implement operating system as a collection of system processes – Useful in processor or multi-computer ... Processes– Operating system software within context of a user process – Process executes in privileged mode when executing operating system code Trang 5353Trang 5454Trang 55Execution of the Operating ... Resources Trang 29Operating System Control Structures • Information about the current status of each process and resource • Tables are constructed for each entity the operating system manages

Ngày tải lên: 09/01/2018, 12:01

... independently by the operating system Process • Dispatching is referred to as a thread or lightweight process • Resource of ownership is referred to as a process or task Multithreading • Operating system ... communicate with each other without invoking the kernel Uses of Threads in a SingleUser Multiprocessing System • • • • Foreground to background work Asynchronous processing Speed of execution Modular ... Windows Process Object 41 Windows Thread Object 42 Windows 2000 Thread States • • • • • • Ready Standby Running Waiting Transition Terminated 43 44 Solaris • Process includes the user’s address space,

Ngày tải lên: 09/01/2018, 12:01

... Chapter 5 Trang 3ConcurrencyTrang 4Difficulties of Concurrency• Sharing of global resources • Operating system managing the allocation of resources optimally • Difficult to locate programming errors ... Sharing resources • Synchronization of multiple processes • Allocation of processor time Trang 9Operating System Concerns• Keep track of various processes • Allocate and deallocate resources – Processor ... 15Mutual Exclusion:Hardware Support • Interrupt Disabling – A process runs until it invokes an operating system service or until it is interrupted – Disabling interrupts guarantees mutual Trang

Ngày tải lên: 09/01/2018, 12:01

... process holds at least one resource needed by the next process in the chain Trang 18Deadlock Prevention • Mutual Exclusion – Must be supported by the operating system • Hold and Wait – Require a process ... for allocation of 200Kbytes, and the following sequence of events occur • Deadlock occurs if both processes progress to their second request Request 70 Kbytes; Request 80 Kbytes; Trang 9Consumable ... compete for system resources or communicate with each other • No efficient solution • Involve conflicting needs for resources by two or more processes Trang 44Trang 6Reusable Resources • Used by only

Ngày tải lên: 09/01/2018, 12:01

... time – Memory protection requirement must be satisfied by the processor (hardware) rather than the operating system (software) • Operating system cannot anticipate all of the memory references ... partition size can be loaded into an available partition – If all partitions are full, the operating system can swap a process out of a partition – A program may not fit in a partition The programmer ... the bounds register • If the address is not within bounds, an interrupt is generated to the operating system 27 Paging • Partition memory into small equal fixed-size chunks and divide each process

Ngày tải lên: 09/01/2018, 12:01

... memory • Operating system places the process in a blocking state Execution of a Program • Piece of process that contains the logical address is brought into main memory – Operating system issues ... of a process not need to be loaded in main memory during execution Execution of a Program • Operating system brings into main memory a few pieces of the program • Resident set - portion of process ... the disk I/O takes place – An interrupt is issued when disk I/O complete which causes the operating system to place the affected process in the Ready state Advantages of Breaking up a Process

Ngày tải lên: 09/01/2018, 12:01

... interrupts– Operating system calls– Signals Trang 9Short-Tem Scheduling Criteria • User-oriented – Response Time • Elapsed time between the submission of a request until there is output. • System-oriented ... Preemptive – Currently running process may be interrupted and moved to the Ready state by the operating system – Allows for better service since any one process cannot monopolize the processor ... Predictability of longer processes is reduced • If estimated time for process not correct, the operating system may abort it • Possibility of starvation for longer processes Trang 2727Trang 28Shortest

Ngày tải lên: 09/01/2018, 12:01

... processors – Such as I/O processor – Controlled by a master processor • Tightly coupled multiprocessing – Processors share main memory – Controlled by operating system Independent Parallelism • Separate ... Failure of master brings down whole system • Master can become a performance bottleneck Assignment of Processes to Processors • Peer architecture – Operating system can execute on any processor ... time-sharing system Coarse and Very CoarseGrained Parallelism • Synchronization among processes at a very gross level • Good for concurrent processes running on a multiprogrammed uniprocessor – Can by

Ngày tải lên: 09/01/2018, 12:01

... taking place in system memory, not user memory – Operating system keeps track of assignment of system buffers to user processes Trang 27I/O BufferingTrang 28Double Buffer • Use two system buffers ... stream of bytes – Used for terminals, printers, communication ports, mouse and other pointing devices, and most other devices that are not secondary Trang 24Single Buffer • Operating system assigns ... Terminal used by system administrator may have a higher priority Trang 8Differences in I/O Devices • Complexity of control • Unit of transfer – Data may be transferred as a stream of bytes for

Ngày tải lên: 09/01/2018, 12:01

... 12 Trang 2File Management• File management system consists of system utility programs that run as privileged applications • Input to applications is by means of a file • Output is saved in a ... file Trang 6969Trang 7171Trang 72Linux Virtual File System• Uniform file system interface to user processes • Represents any conceivable file system’s general feature and behavior • Assumes files ... to be performed • Concerned with scheduling access to optimize performance • Part of the operating system Trang 17Logical I/O • Enables users and applications to access records • Provides general-purpose

Ngày tải lên: 09/01/2018, 12:01

... 2Distributed Capabilities• Communications architectures computers • Network operating system system • Distributed operating system Trang 3The Need for a Protocol Architecture • Computer communications ... Protocol ArchitectureTrang 8Network Access Layer• Concerned with the exchange of data between an end system and the network • Different standards – Circuit switching – Packet switching (frame relay)

Ngày tải lên: 09/01/2018, 12:02

... private • Share via access limitation – Operating system checks the permissibility of each access by a specific user to a specific object – Operating system acts as the guard Trang 18• Share ... independently of some application program, utility, or system program • Independent – Self-contained programs that can be scheduled and run by the operating system Trang 43• Entry point into a program ... profile that specifies permissible operations and file accesses • Operating system enforces these rules • Database management system controls access to specific records or portions of records

Ngày tải lên: 09/01/2018, 12:02