Presentation is loading. Please wait.

Presentation is loading. Please wait.

Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum.

Similar presentations


Presentation on theme: "Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum."— Presentation transcript:

1 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 1 CS U480: Systems & Networks 1. Introduction Donghui Zhang

2 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 2 Syllabus Instructor: Donghui Zhang Class page linked from my home page:

3 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 3 Your Background CSU380: Computer organization System architecture: Processors, memory, I/O devices Processor architecture: ALU, instruction execution Assembly-level programming C/C++ programming Familiarity with the C language and the standard C library Please consult with me if you are unsure your background is sufficient

4 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 4 Why Programming For CS: must. A pilot must know how to fly an airplane. For IS: also important. A project manager needs to have technical background. Bill Gates used to be a superb programmer. Guest speaker: Prof. Hafner.

5 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 5 Why C (and not Java) Talked with Mr. Feuer and Prof. Hafner. We provide guidance to what you should learn. (If you say give us A without any exam or project…) Most OS are implemented in C. Java hides many low-level details. This is a place to strengthen your C skills.

6 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 6 What is an Operating System? An operating system is a program that acts as an intermediary between a user of a computer and the computer hardware. Goals: Execute user programs and make solving user problems easier. Make the computer system convenient to use. Performance measures: Throughput: The total amount of work done over a period of time. Turnaround: The total time it takes to complete a job.

7 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 7 Concept Map CPU ALU Registers Peripherals Disks Keyboard Mouse Display Applications GUI Console OS Memory

8 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 8 Software Layers Application c = getc() Library read(…) Operating System kb_driver_read(…) Device driver read_device(…)

9 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 9 Compilation vs. Execution During compilation, statements in higher-level languages are converted into machine code During execution, machine code is interpreted by a processor Memory Compiler High-level language program Assembly language Assembler Machine code Link editor Libraries of Machine code Executable Shared Libraries Operating System Device Drivers

10 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 10 Evolution of the OS In the beginning Whirlwind at MIT PDP-1 from DEC Altair from MITS Program stored in a hardware patch board or toggled in using switches Program can access all of memory Program starts at location zero Loading programs by hand is slow and error-prone and painful, so... Memory Program 0 n

11 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 11 Create a very short program to load longer programs Toggle in bootstrap loader Primitive loader may load in program or a more complex loader to read from cards or tape Loading from cards is very slow, often took longer to load than to run, wasting (expensive) processor cycles, so... Memory Loader Program 0 n Evolution of the OS: The Loader

12 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 12 Jobs are spooled on tape While one batch of jobs is running, card reader writes next batch of jobs on tape Jobs are read sequentially from tape into memory Tape is still relatively slow compared to processing Memory Batch Loader Program 0 n Evolution of the OS: Batch Processing

13 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 13 With the introduction of programming languages, a translator is needed to convert a program into machine code When a program is stored on cards in the programming language, e.g., assembler or Fortran, it must be translated before it can be run Example: To run a program written in Fortran 1. Load (machine code for) Fortran compiler 2. Run compiler: Compiler reads program, writes machine code 3. Load (machine code for) program 4. Run program The Concept of a Job

14 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 14 Load next program while previous program is running But now both programs cant begin at address zero (in fact, starting address isnt known in advance) Solutions? Programs that perform lots of I/O waste (expensive) processor cycles Memory Loader Program 1 Program 2 0 n Evolution of the OS: Multiprogramming

15 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 15 Share execution time among programs When one program starts I/O, let the other run. What is needed to switch from one program to another? A program bug in one program can overwrite another program, or the system programs and data, so... Memory Loader + scheduler Program 1 Program 2 System data 0 n Evolution of the OS: Multitasking

16 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 16 Run programs in separate address spaces System programs need to cross address spaces. System runs in privileged mode. The more programs in memory, the less memory available for each program, so... Memory Loader, scheduler, memory mgr Program 1 Program 2 System data Program 3 0 n Evolution of the OS: Protection

17 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 17 Address space implemented in both main and secondary memory Broken into pages A programs address space is a set of pages. The address space for a program may be larger than main memory! Pages are swapped in and out of main memory as needed. Memory Loader, scheduler, memory mgr, resource mgr Disk 0 n Evolution of the OS: Virtual Memory

18 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 18 OS Diversity Great diversity of programmable hardware Super computers: simulation, scene generation, data mining Servers: database, web, video Personal: desktop, laptop Embedded: PDA, phone, media device Nature of the OS depends on Application mix Hardware capability Real-time requirements With the proliferation of embedded systems, most processors do not run a general purpose OS

19 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 19 OSes are complex programs developed over many years by many people They confront common problems that reappear in other contexts The problems have been formalized A variety of solutions have been proposed and implemented Choosing a solution requires evaluating tradeoffs of space, time, and complexity OSes are a rich source of well-designed sample programs We will study OSes by exploring common components Understand the motivation for each component Understand the tradeoffs for each implementation

20 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 20 Common System Components Process Management Main-Memory Management File System I/O System Network Management Lets take a high-level tour of these components

21 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 21 Process Management A process is a program in execution To accomplish its task, a process needs certain resources: CPU time Memory Files I/O devices. The OS is responsible for the following activities in connection with processes: Process creation and deletion Process suspension and resumption Mechanisms for: Process synchronization Inter-process communication

22 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 22 From Program to Process Memory Compiler High-level language program Assembly language Assembler Machine code Link editor Libraries of Machine code Executable Shared Libraries Operating System Device Drivers Program Process

23 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 23 Memory Management Main memory is a large array of words Each word (or, often byte) has its own address Data in memory is shared by the CPU and I/O devices Main memory is (usually) volatile It loses its contents in the case of system failure. The OS is responsible for the following activities in connection with memory management: Keep track of which parts of memory are currently being used and by whom. Decide which processes to load when memory space becomes available. Allocate and deallocate memory space as needed.

24 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 24 Memory Management (cont.) Memory Loader, scheduler, memory mgr Program 1 Program 2 System data Program 3 0 n

25 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 25 Secondary-Storage Management Secondary storage is (usually) a large array of blocks Each block has its own address Data is moved between main memory and secondary storage in units of blocks Secondary storage is non-volatile and can be very large Disks are the most common in general purpose systems Memory cards and stick are common on portable devices The OS is responsible for the following activities in connection with secondary storage management: Free space management Storage allocation For disks, scheduling of block transfers

26 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 26 Secondary-Storage Management (cont.) Memory Loader, scheduler, memory mgr, resource mgr Disk 0 n

27 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 27 File Management A file is a collection of related information Files are stored within a file system From the view of most systems, a file is an array of bytes The OS is responsible for the following activities in connections with file management: File creation and deletion Directory creation and deletion Support of primitives for manipulating files and directories Mapping files onto secondary storage. File backup on stable (nonvolatile) storage media

28 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 28 I/O System Management Input/Output refers to the movement of data between main memory and peripheral devices Devices vary widely in their operation and behavior Devices are partitioned into classes to factor common behavior A device driver translates between general OS operations and device-specific commands I/O managements consists of A buffer-caching system A general device-driver interface Drivers for specific hardware devices

29 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 29 I/O System Management (cont.)

30 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 30 Network Management Networking allows distinct computer systems to exchange data Communication takes place using a protocol Networked computers vary widely in their degree of coupling: They may share a common OS and processes may be visible across systems They may share nothing except a communication port Networking allows users to access to non-local resources, allowing: Computation speed-up, through special purpose hardware or parallel processing Availability of data from other systems Enhanced reliability through redundancy

31 Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum 31 Network Management (cont.)


Download ppt "Adapted from the slides prepared by Alan Feuer Some material from Operating System Concepts by Silberschatz et. al. and Modern Operating Systems by Tanenbaum."

Similar presentations


Ads by Google