Computer System Management - Troubleshooting and Operating

System

Amarjeet Singh

August 11, 2011

Partly adopted from Computer System Management Slides by Navpreet Singh

Logistics

Lab sessions:

Did you find it useful?

BIOS will be done in the next lab session

Handout for the next lab session uploaded on the course website

Video for the next lab session uploaded on youtube channel

If you got your new laptop, please bring it to the next lab session so that you can install Ubuntu on your laptop itself rather than on the lab machine

Course webpage updated:

Last lecture slides

Notes on PCI, CD RW

Logistics

Learn-it-yourself:

Topics will be put on the course website by next week

If you want to do something outside the list, make sure that it involves using some hardware/software utility and is not purely a reading topic

For each topic, I will also provide a list of expectations from each topic in due course of time as well

To be done in groups of 3

You have to create a video, preferably less than 10 minutes, but surely not more than 15 minutes

Make sure to create a proper script and then make a proper video for that topic – should be good enough for students outside to also watch and learn

Honor code!

Any exam or submission, I will be checking for copying/cheating

We have software that can with a high degree of accuracy provide us with sources from where the text is copied

Make sure you don’t copy/cheat

First act - reduction in one letter grade

Second act - F in the course

Revision - I

Computer Model - What are the 4 building blocks?

What are the 4 Primary CPU operations?

How is memory in a computer structured hierarchically?

What different parameters does the speed of computer depend on?

How is information stored on a HDD?

How does DVD store more data than a CD?

What are the typical DC output values of the computer power supply?

What is the difference between mechanical and optical mouse?

What is the maximum number of connected devices allowed by the USB standard?

Quiz - I

In the feedback sheet you are going to provide, also add the answers to the following questions:

1. When I specify the serial port configuration as 19200-8-N-1, what does each field signify?

2. Write the one bit parity (even parity) for the following sequence:

2.a 10010111

2.b 01011010

3. Write two factors that lead to PCI-e being faster than PCI

4. How are CD/DVD drives different from HDD in terms of rotational velocity?

Troubleshooting - POST

Power On Self Test (POST) - Tests the computer to make sure all the hardware is working properly

Errors found during the test are stored/reported through visual/auditory means

Successful completion usually reported using a single beep

Typical components tested - Power supply, CPU, CMOS, Memory interface, I/O bus interface

Failure of any test returns irregular POST through a beep code (specific to the BIOS)

Error also used to be published to a fixed I/O port address and read by POST card

Troubleshooting - Free Diagnostic Tools

Memory Interface

Windows memory test - part of Vista and Windows 7

Memtest86 - http://www.memtest86.com

Motherboard and CPU:

Hot CPU Tester - http://www.memtest86.com

CPU temperature monitor utilities

HWMonitor - http://www.cpuid.com/hwmonitor.php

Core Temp - http://www. alcpu.com/CoreTemp

SpeedFan - http://www.almico.com/sfdownload.php

Hard Disk Drive: Scandisk, Chkdsk - Pre-installed in windows

TestDisk - http://www.cgsecurity.org/wiki/TestDisk

HDD health - http://www.panterasoft.com

CD/DVD: CD Roller - http://www.cdroller.com

CD Check - http://www.kvipu.com/CDCheck

Booting up

So far we have come across BIOS which is the first piece of software that gets executed when you start the computer

Lets move on…

We need to start the Operating System stored in hard disk drive

Computer executes BIOS stored in ROM that performs the POST and initiates the Operating System - Boot loader

Often multi-stage: BIOS executes a small program in the boot device

Also called Master Boot Record (MBR): Space constrained (446 bytes)

MBR being limited size points to another location where detailed boot information is stored (can be located anywhere on the disk)

Stage architecture allows boot loader to be larger in size

Second stage loads OS and transfers execution to it

Boot Loader

Different types of second stage boot loader - Grand Unified Bootloader (GRUB), BOOTMGR, Linux Loader (LILO), NT Loader (NTLDR)

For a multi-boot system, always install Windows first, on the first hard disk, in the first partition (Three firsts)

Windows assumes it is the only operating system in the world, and does not try to live with existing information present in the MBR - overwrites it

Learn-it-yourself activity

Remember that if you spoil your boot loader, you are risking your complete system since the address from where the OS should start is spoiled in that case

Be careful!

Operating System (OS)

Let us look at some of the definitions from the class:

Interface/link/intermediate-language/GUI between the machine/ hardware/system and the user/us

Platform/software for other program/application to run

Medium between user and software through which better use of hardware and software is possible

Operates the system

In which everything runs

Main part which performs the operations/calculations and processes the result

Manages files and folders

Helps us communicate with computer in a user friendly way

Operating System (OS)

OS is a set of system software programs that regulate how the application software controls the hardware and how the users control the program

Acts as an intermediary between application software and actual hardware to perform hardware functions such as input/output and memory space allocation

Primary OS

Windows (NT Family): First public Release 1993, Latest stable version Windows 8 (2012)

Linux: 1992, Linux Kernel 3.5.2 (2012)

MAC OS X: 2001, 10.8 (2012) - Latest version OS X Mountain Lion

Image Source: http://en.wikipedia.org/wiki/Operating_system

Operating System (OS)

Image Source: Wikipedia

OS components

User Interface: for human input

Command-line interface: commands are typed out line by line (eg. Terminal)

Graphical User Interface (GUI): visual environment (eg. Explorer)

GUI primary components

Windows: Information is organized in windows

Icons: Information represented by icons

Menu: Available commands are compiled together in menu

Pointing device: position of cursor controlled by a physical input device

Called WIMP paradigm

Are all GUI WIMP?

Image Source: http://en.wikipedia.org/wiki/Operating_system

OS components

User Input to an application initiates interaction with the computer hardware devices (CPU, memory, I/O devices)

Since there will be multiple programs running in parallel - hardware resources need to be controlled (task of OS)

Executing a program results in a process in OS (ps in linux, Task Manager in Windows)

Memory and other resources, together with a priority are assigned to each process

Process continues interaction with user and other devices

Image Source: http://en.wikipedia.org/wiki/Operating_system

OS components

All this is done by Kernel in OS

Bridge between applications and actual data processing done at the hardware level

Manages system’s resources

Provides lowest level abstraction for hardware resources

Resources consist of CPU, memory and I/O devices

Image Source: http://en.wikipedia.org/wiki/Operating_system

How does kernel manage multiple resources?

Poll sources of inputs (programs/ hardware) for events that require action

Let the sources tell whenever an event occurs - interrupts

OS components

Kernel is specific to OS and allows interfacing with variety of hardware resources

Need a way for these resources to tell OS how to interface with them - job of a Device Driver

Since each hardware device interacts in a specified manner, device driver will be specific to a device and the OS

Communicates with the hardware through communication subsystem to which the hardware is connected (eg. ?)

Acts as a translator

Handles interrupts both from the application and hardware

Usually comes with the hardware (installation CD)

Either loaded at boot time or on request

OS components

Image Source: http://dlc.sun.com/

OS components

Image Source: http://www.roma1.infn.it

MS-DOS

Microsoft Disk Operating System

Primary OS for personal computers until mid 90s

Command-line interface

Runs on machines with the Intel x86 or compatible CPUs, mainly the IBM PC and clones

Single-user, single-task OS with basic kernel functions that are non-reentrant: only one program at a time can use them

What does that mean in terms of interrupts?

All version of MS Windows have MS-DOS like command line interface

Accessed by typing “cmd” in “run”

Windows Operating System

Microsoft first introduced an operating environment named Windows in November 1985

As an add-on to MS-DOS

16 Bit OS running on top of DOS providing Multitasking and GUI

Windows 3.0 (1990), Windows Workgroup 3.11 (1992)

Improved the design

16/32 Bit OS

Windows 3.1 had Internet Explorer browser as part of OS

Windows 95, Windows 98, Windows ME (2000)

32 Bit OS

Used FAT File System

Supported DOS as well

Windows Operating System

NTFS introduced in 1993 as the file system for Windows NT server

Later adopted as default File system for all later releases of Windows client and server OS

Windows NT 4.0 (1996) was the true Multi-User and Multi-Tasking OS based on NTFS File System; Later replaced by Windows 2000

Windows XP, Vista, 2003, 2008, Windows 7 and Windows 8 are all available in 32 bit and 64 bit versions

Mobile version - Windows mobile (renamed as Windows Phone with launch of Windows Phone 7)

Approx. 3% market share of smartphones

Linux Operating System

Free and open source software

Several versions - both commercial (Redhat server edition, Xandros) and free (Ubuntu, Fedora, Mint, openSUSE)

Modular, unix-like OS

Unix was first conceived and implemented in 1969 in Bell Labs

Was not free initially

GNU started in 1983 with the goal of complete Unix-compatible software system composed entirely of free software

MINIX - (Minimal Unix-like) OS designed for education in computer science

Limited use of MINIX prompted development of Linux in 1991

Linux Operating System

GUI for most distributions built over X Window System

WINE (free and open source) provides Windows compatibility layer to run unmodified Windows applications in Linux

Embedded Linux - used in a lot of embedded systems including smartphones

MAC OS X Operating System

Unix based OS and GUI developed, marketed and sold by Apple

First release in 2001

Initially restricted to run on PowerPC processors

Transition to Intel processor announced in 2005

In 2009, completely dropped support for PowerPC

Supports both 32 and 64 bit versions

iOS: Apple’s OS for mobile devices (iPhone, iPod Touch, iPad)

Released in 2007

Learning

What did you learn today? Each group to write on a sheet of paper and submit

me with their names • This is also your attendance for the day