Sistem Operasi “Overview”

Materi Konsep dasar sistem operasi, khususnya komponen-komponen pembentuk suatu sistem operasi. Konsep penjadwalan CPU, pengaturan memory, dan sistem I/O

Buku Ed 7 dan 8 http://codex.cs.yale.edu/avi/os-book/OS8/os8c/slide-dir/index.html

Buku terbaru

Pengantar Sistem Operasi Sebuah program yang merupakan perantara antara pengguna komputer dan hardware komputer Komputer = tubuh, SO = roh SO digunakan dalam hal: Mengeksekusi program dan membantu menyediakan lingkungan bagi program yang mudah untuk berinteraksi dengan system resource

Tujuan OS Convenience : user merasakan kemudahan dan kenyamanan dalam penggunaan Efficiency : resources system harus dapat di utilisasi semaksimal mungkin Robustness : kehandalan sistem proteksi terhadap kesalahan dari user / sistem Evolution : memudahkan pengembangan, mendukung sistem baru dan program aplikasi yang berkembang

Fungsi Dasar Sistem Operasi start the computer provide a user interface manage programs administer security manage memory control a network provide file management and other utilities monitor performance establish an Internet connection schedule jobs and configure devices p. 392 Fig. 8-1

Fungsi Dasar Sistem Operasi File and Folder Management Applications Management Support for built-in utility programs Computer hardware control

Layanan Sistem Operasi Menyediakan user interface Menyediakan program execution Menyediakan I/O operations Menyediakan file-system manipulation Menyediakan system communications / networking Mampu melakukan error detection Mampu melakukan resource Sharing Ada fasilitas security Fasilitas accounting system

Struktur Sistem Operasi Kernel File Management System User Interface

Klasifikasi Sistem Operasi when two or more users can work with programs and share peripheral devices (printer, scanner, fax) Multiuser multiple applications operated at the same time Multitasking more than one CPUs that can be shared Multiprocessing smaller parts of a program are loaded when needed by OS Multithreading

Jenis Platform & OS Microcomputers: Unix, Windows, Linux Mainframe: IBM, Unix Supercomputer: IRIX, Linux Workstation, server: Linux, Windows Networking: Linux, Netware, Windows PDA: Blackberry, Linux, Palm, Windows Mobile Smarphone: Symbian, Linux, Windows Mobile, Android, RIM

Most Popular Desktop OS

Popular Mobile OS

Mainframe OS vs PC OS the basic difference is that @ mainframe platform u can run more than one OS at a time on same machine but this feature not available at PC OS. Mainframe OS are targeted to handle hundreds of users at a time whereas PC OS is targeted for a single user.  a mainframe operating system will probably need to service many users at the same time, whereas a PC operating system normally only has to worry about one user at a time. 

Mainframes Mainframes run multiple operating systems and operate not as a single computer but as a number of virtual machines. They are typically manufactured by large companies for large-scale computing purposes

Mainframes z/OS from IBM While IBM System z™ servers are supported by a number of different operating systems, their most advanced features are powered by z/OS http://www-03.ibm.com/systems/z/os/zos/

Virtualization

Clouds

Embedded Systems Embedded systems are special-purpose systems in which the computer is completely encapsulated by the device it controls. Embedded systems perform pre-defined tasks that have very specific requirements. Real-time operating systems are embedded systems with certain time requirements

Embedded Systems Symbian, Bada and Android OS for smartphone Cisco IOS for router and switch iPodLinux for ipods Windows CE.Net Windows Mobile 2003

Unix-like OS The operating system Unix was developed in 1960 by a group of AT&T employees. Free Unix-like operating systems can be used, studied, modified and redistributed by anyone with no restrictions.

Unix-like OS It's a diverse group of operating systems with several major sub-categories including BSD, and Linux. Unix like operating systems run on a variety of computers but more frequently on server systems and in academic and engineering environments due to high stability for any kind of processing

Unix-like OS Ubuntu FreeBSD openSUSE Debian Fedora

Mac OS Apple's Macintosh OS is an operating system with a very innovative and unique design. The history of the company behind it, Apple, that's been around since 1976 is fascinating and so is its cool operating system Mac OS. Leopard merupakan versi Mac OS terbaru (http://www.apple.com/macosx/)

Microsoft OS Windows Version Year Released Windows 3.x 1990 Windows NT 3.1 1993 Windows 95 1995 Windows NT WS 4.0 1996 Windows 98 1998 Windows ME 2000 Windows 2000 Professional 2000 Windows XP 2001 Windows Vista 2006 Windows 7 2012 Windows 8 2013

Network OS Sistem Operasi yang berbasis jaringan Contoh: A Network Operating System (NOS) is a software program that controls other software and hardware running on a network. It also allows multiple computers, known as networkcomputers, to communicate with one central hub and each other to share resources, run applications, and send messages. Such a system can consist of a wireless network, Local AreaNetwork (LAN), or even two or three computer networks connected together. Administrators running these networks typically have training in different network operating systems. Contoh: Novell Netware Windows Server 2003 Linux Solaris (Sun)

WebOS The WebOS (Web Operating System) represent a new form of virtual operating system that runs directly in your browser. The main advantages of a web operating system is that you can access it from anywhere but it's very arguable if it's really an operating system or not because it runs over a browser window and have no relation whatsoever with the hardware and its drivers. You will still need an operating system to run a WebOS.

Web OS Architecture

WebOS DesktopTwo (http://desktoptwo.com) G.ho.st (http://g.ho.st) YouOS (http://youos.com) BrowserOS (http://oos.cc) eyeOS (http://eyeos.org)

DesktopTwo

youOS

eyeOS

OS mobile

Komponen-komponen Sistem Komputer Perangkat keras CPU, RAM, storage (harddisk, floppy disk, CDROM, dsb), piranti I/O (printer, scanner, dsb) Operating System Mengontrol dan mengkoordinasikan penggunaan hardware dari berbagai program aplikasi dan user Program-program aplikasi Pengaturan penggunaan system resources untuk pemecahan problem kebutuhan user (kompiler, sistem basis data, games, dan program-program untuk bisnis) User Orang, mesin, atau komputer lain

4 komponen sistem komputer

Process Process – program dalam mode eksekusi Eksekusi program harus pada suatu waktu yang sekuensial

Foreground vs Background Process

Thread Process vs Thread Keuntungan: Process: suatu aplikasi yg running Thread: beberapa kegiatan dlm 1 proses Keuntungan: Responsiveness Resource Sharing Economy Utilization of Multi Processors Architectures

Single vs Multithread

Firefox vs Chrome

Firefox vs Chrome

Schedulling Memilih proses mana dari memory yang siap diekseskusi dan mengalokasikan resource/CPU kepadanya. Keputusan penjadwalan CPU mungkin terjadi waktu proses: 1. Switches from running to waiting state 2. Switches from running to ready state 3. Switches from waiting to ready 4. Terminates Scheduling no 1 dan 4 adalah non-preemptive Selainnya bersifat preemptive preemption is the act of temporarily interrupting a task being carried out by a computer system, without requiring its cooperation, and with the intention of resuming the task at a later time.

Synchronization Why process synchronization needed? Akses secara konkuren (hampir bersamaan) terhadap data yang bersifat shared, dapat menyebabkan data tidak konsisten Terjadi race condition Banyak algoritma sinkronisasi FCFS (First Come First Served) SJF (Shortest Job First) preemptive dan non preemptive RR (Round Robin)

Deadlock Pada multiprogramming, beberapa proses hanya memiliki resource yang terbatas. Jika tidak ada resource yang tersedia, process harus menunggu 2 types of resource: Preempt-able, ex: memory Non-preempt able, ex: printer Harus menunggu jika resource tidak boleh dipakai Permintaan proses mungkin diblok Mungkin bisa gagal dengan kode error tertentu

Memory Program harus dibawa (dari disk) ke memory dan ditempatkan pada alamat tertentu agar dapat berjalan Main memory dan registers adalah satu-satunya tempat penyimpanan yang dapat langsung diakses oleh CPU Register mengakses dalam 1 CPU clock (bisa kurang) Main memory mengakses dalam bnyk cycles / clock Cache berada diantara main memory dan CPU registers Protection of memory dibutuhkan untuk menjamin agar operasinya benars

Virtual Memory Virtual memory – pemisahan antara memori logis dari memori fisik. Hanya bagian dari program yang dibutuhkan saja yang harus ada dalam memory untuk dieksekusi Logical address space dapat lebih besar daripada physical address space Memperbolehkan address spaces untuk disharing oleh beberapa processes Menyebabkan pembuatan proses secara lebih efisien

Virtual Memory Page Replacement Algoritma FIFO Algoritma Optimal Algoritma LRU Algoritma Perkiraan LRU

Konsep File File adalah kumpulan informasi yang berhubungan dan tersimpan dalam secondary storage Tipe: Data (character, numeric, binary) Program Direktori Device Sifat: persistance, big size, dan sharability

File Manager

Atribut File Name – disimpan dalam human readable name Identifier – unique tag (number) dalam file system Type – dibutuhkan oleh sistem (ex: .txt) Location – pointer to file location di harddisk Size – current file size Protection – controls siapa yang reading, writing, executing Time, date, and user identification – data untuk protection, security, and usage monitoring Information about files are kept in the directory structure, which is maintained on the disk

File properties

Perangkat I/O Perangkat block: Perangkat character: Meliputi berbagai disk drive Perintah baca, tulis, pencarian data Dapat digunakan untuk mengakses memory pada disk Perangkat character: Contoh: keyboard, mouse Perintah menulis, mengambil Dapat dibuat library pengakses data per-baris Perangkat jaringan: Socket: penghubung komputer dengan jaringan. Komunikasi antar komputer dilakukan melalui socket.

Characteristics of I/O Devices

MS-DOS What is MS-DOS? MS-DOS stands for Microsoft Disk Operating System. MS-DOS controls the computer’s hardware and provides an environment for programs to run. Run in single user, stand alone desktop computer Simple, only have few instructions For Intel 8086, 8088, 80186, & 80286

Windows XP Architecture

Linux Architecture

Alternatives OS

Tugas kelompok Penjadwalan Proses (Kelompok 1) Sinkronisasi Proses (Kelompok 2) Deadlock (Kelompok 3) Manajemen Memori Nyata (Kelompok 4) Manajemen Memori Virtual (Kelompok 5) Manajemen Input / Output (Kelompok 6) Sistem Manajemen File (Kelompok 7) Implementasi Sistem File (Kelompok 8)