Lecture 2: Hardware Review
Review from last lecture OS is everywhere Electronic devices in our daily life Natural security A critical layer between hardware and applications An extended machine Resource manager
Introduction A computer system consists of hardware system programs application programs
What is an Operating System? It is an extended machine Hides the messy details which must be performed Presents user with a virtual machine, easy to use abstractions It is a resource manager Each program gets time with the resource Each program gets space on the resource
Overview of this lecture OS history OS Zoo Computer hardware review
Operating Systems History 1945-60: Batch Systems – Cards 1960-70: Spooling Batch Systems – Tapes 1960- : Multiprogramming 1970- : Timesharing 1990- : Real-time, Distributed 2005-: WebOS/IoT/Mobile/Wearable/Implantable/Etc. All programming was done in absolute machine language, vacuum tubes vs transistor
The Operating System Zoo Personal computer operating systems Single user (usually) MS-DOS, Windows, Linux Server operating systems Focus on networking Linux, SunOS, Windows NT Multiprocessor operating systems Real-time operating systems Hard versus soft real-time OS Embedded operating systems Memory, power constraints Smart card operating systems Extreme resource constraints Mobile Operating Systems Android, iOS
Computer Hardware Review Monitor Bus Components of a simple personal computer
CPU (a) A three-stage pipeline (b) A superscalar CPU
Multicore and Multithreading CPU Multiple threads in a single core Multiple cores
Memory Typical memory hierarchy numbers shown are rough approximations
Structure of a disk drive
Solid State Drive (SSD) Flash Memory based on NAND Cell: Simplest Structure, Array When a charge is applied, the electrons tunnel into the cell through the dielectric barrier. When the charge is stopped the electrons are trapped in the cell. The resulting positive or negative charge can then be measured. King-Vidas-DFRWS2011 Presentation
SSD vs. HDD From N. Memon’s Slides
I/O Devices (a) (b) (a) Steps in starting an I/O device and getting an interrupt (b) How the CPU is interrupted
Structure of a large Pentium system An Example: Pentium Structure of a large Pentium system