Operating System

2009-09-17T03:11:00.000-07:00

Installation Process Mandriva Linux

If you like your new environment, you can install it on your system. This is very easy.

Start installation

Click on the install icon on desktop. Installation process starts.

System partitions

You will be asked then to choose the way you want to manage disk space to install Mandriva Linux on your system. You can either choose an automatic way which is easier if you are not used to. You can also choose custom way which will allow you to manage all your partitions as you want.

Before rebooting your system

After installation on your hard disk, you will be asked to clean your new system. In order to support as many languages and hardwares as possible, Mandriva Linux One CD provides many of drivers and languages packages. You can clean this and get more space available. Validate that step.

Remove the One CD from the reader and reboot.

Reboot and configure Mandriva Linux

Each time you will boot your system, you will get a boot menu. It will allow you for example to choose either Mandriva Linux or Windows.

Finally last steps will ask you to configure Mandriva Linux: keyboard, timezone, network connection, users creation.

2009-09-17T03:09:00.000-07:00

Solaris installation

Step by step guide to Solaris installation

1. Before you begin

For Solaris installation on standalone Sun machine you need the following besides sun cpu :

A) Sun Monitor and Sun Keyboard

For carrying the installation through the serial port A of Sun (ttya)

Dumb Terminal or PC with serial port communication software like HyperTerminal

AND

A null modem cable ( Pin 2 & 3 crossed 5 common ground in 9 Pin to 9 pin ; Pin 7 is common ground in 25 Pin connector ) connecting sun's serial port A with PC serial port.

B) You will also require a IP address, netmask and a host name for your system.

2. Getting Started

Installation starts at OK> prompt & you can get to ok> using any of the following method :

1. by pressing Stop A key sequence on a Sun Keyboard.

2. typing #init 0 if your system boots up directly .

3. Pressing ctrl-break or shift-break on a pc keyboard if using pc as

console through serial port.

4. If auto-boot feature is enabled system directly boots up

and gives you a # prompt .You can disable auto-boot so next time it

stays at ok prompt for starting installation.

#/usr/platform/sun4u/bin/eeprom auto-boot?=false

reboot the system.

3. Starting the installation

Insert the installation media - OS CD in CD drive and type boot cdrom at ok> prompt .

Ok>boot cdrom

The first phase begins with system identification and gathers information about the system from the the user .System starts booting up and after initialization it asks for language and locale also terminal type in case of PC/terminal

Select your locale and DEC VT100 terminal type for terminal selection

Further installation through the terminal require response to the

selections through ESC and function keys and space bar which are

mentioned on the installation screen.

On the next screens, you are to identify the system as networked or non-networked, and set the default time zone and date/time. After this following host information is required :

A) A host name for the system

B) Whether the system is networked if yes you will have to

provide the IP address & netmask of this machine.

Next you will be asked to select the name services

Name services

[ ] NIS+

[ ] NIS

[ ] DNS

[X ] None

Select the service if you have complete details like domain names etc or select none to configure after installation.

You have to select a distribution type from among the choices choices

4. OS distribution & Disk configuration

After identification is complete the installation process proceeds on to the OS and disk configuration and need your input for these settings. Selection depends on role of your machine

Typical space requirement for Solaris 7 is given here.

[ ] Entire Distribution plus OEM support 64-bit 1242.00 MB (F4 to Customize

[X] Entire Distribution 64-bit .....…...….1215.00 MB

[ ] Developer System Support 64-bit.... 1154.00 MB

[ ] End User System Support 64-bit .….. 765.00 MB

[ ] Core System Support .............. .334.00 MB

Entire distribution with OEM has all software with some third party software
Entire distribution has all software without third party software .
Developer system has run time libraries for C software etc.
End user has X windows and CDE environment .
Core system is without X windows softwares etc.

If you are not sure select entire distribution.

You will be presented with choice to select the boot disk among the disks present in the system ,unless you have reasons select the c0t0d0 at boot disk.

[ X ] c0t0d0 (17269 MB) boot disk 17269 MB

[ ] c0t1d0 (17269 MB) 17269 MB

overlap partition represents entire disk and is slice s2 of the disk.

If any of the disk contain a preexisting partition you will be given a choice to preserve the partition .

Next the current layout is given ( if existing ) and you are asked to select between Automatic and Custom layout of disk partitions.

Automatic layout make a single partition of entire boot disk .
Customize option gives and option to create the partitions and select the sizes .

Things to keep in mind while doing interactive or custom installation

Additional space is required in /var & /home if server is to handle mail and printing as mail and print files are formed in /var & if the user home directories are to be located on /home partition

A sample partition table may look like following .

File system/Mount point Disk/Slice Size

---------------------------------------

/ c0t0d0s0 300 MB

swap c0t0d0s1 2000 MB

overlap c0t0d0s2 17269 MB

/usr c0t0d0s3 2000 MB

/opt c0t0d0s4 1000 MB

/var c0t0d0s5 1000 MB

> The swap partition size depends on the size of RAM in the system if you are not sure of its size keep it double the RAM or more than RAM in the system.

> If you are not sure of individual partition sizes of / , /usr /opt & /var make one partition as / and keep its size sufficiently higher than the distribution size you have selected in earlier steps . Always keep in mind the future software that you might have to install like compilers applications etc and log files that will be generated and accumulate in /var directory or partition.

After you have specified the partition sizes it gives summary and error if any

Installation Option: Initial

Boot Device: c0t0d0s0

Client Services: None

Software: Solaris 2.7, Entire Distribution

File System and Disk Layout:

/ c0t0d0s0 300 MB

swap c0t0d0s1 2000 MB

/usr c0t0d0s3 2000 MB

/opt c0t0d0s4 1000 MB

/var c0t0d0s5 1000 MB

one more question is asked about rebooting

[X] Auto Reboot

[ ] Manual Reboot

Afterwards it starts configuring disk making partitions and installing software indicating the progress in a table .

MBytes Installed: 700.66

MBytes Remaining: 0.00

Installing:

0 20 40 60 80 100

After the installation is complete it customizes system files , devices ,logs , installs patches which are there in OS CD for that release. You can install recommended latest patches later

System then reboots or ask you to reboot depending upon the choice selected earlier .

5. After Installation

After rebooting it asks for new root passed and comes to console prompt where you can login as root install patches ,additional softwares , make user etc. etc.

2009-09-17T02:40:00.000-07:00

Install Windows 2000 Server

Step #1: Plan your installation

When you run the Windows 2000 Server Setup program, you must provide information about how to install and configure the operating system. Thorough planning can make your installation of W2K more efficient by helping you to avoid potential problems during installation. An understanding of the configuration options will also help to ensure that you have properly configured your system.

I won't go into that part right now but here are some of the most important things you should take into consideration when planning for your Windows Server 2000 installation:

Check System Requirements

Check Hardware and Software Compatibility

Determine Disk Partitioning Options

Choose the Appropriate File System: FAT, FAT32, NTFS

Decide on a Workgroup or Domain Installation

Complete a Pre-Installation Checklist

After you made sure you can go on, start the installation process.

Step #2: Beginning the installation process

You can install Windows 2000 Server in several methods - all are valid and good, it all depends upon your needs and your limitations.

Manual installations usually come in 3 flavors:

Boot from CD - No existing partition is required.

Boot from the 4 Setup Boot Disks, then insert the CD - No existing partition is required.

Boot from an MS-DOS startup floppy, go to the command prompt, create a 4GB FAT32 partition with FDISK, reboot, format the C partition you've created, then go to the CD drive, go into the I386 folder, and run the WINNT.EXE command.

Run an already installed OS, such as Windows NT 4.0 Server. From within NT 4.0 go to the I386 folder in the W2K installation CD and run the WINNT32.EXE command.

If you want to upgrade a desktop OS such as Windows 98 into Windows 2000 Professional you can follow the same procedure as above (You cannot upgrade Windows 98 into W2K Server).

There are other non-manual installation methods, such as using an unattended file along with a uniqueness database file, using Sysprep, using RIS or even running unattended installations from within the CD itself, but we won't go into that right now.

It doesn't matter how you run the setup process, but the moment it runs - all setup methods look alike.

Step #3: The text-based portion of the Setup program

The setup process begins loading a blue-looking text screen (not GUI). In that phase you will be asked to accept the EULA and choose a partition on which to install W2K, and if that partition is new, you'll be asked to format it by using either FAT, FAT32 or NTFS.

1. Start the computer from the CD.

2. You can press F6 if you need to install additional SCSI adapters or other mass-storage devices. If you do you will be asked to supply a floppy disk with the drivers and you CANNOT browse it (or a CD for that matter). Make sure you have one handy.

3. Setup will load all the needed files and drivers.

4. Select To Setup W2K Now. If you want, and if you have a previous installation of the OS, you can try to fix it by pressing R. If not, just press ENTER.

5. In case your server is a new one, or it is using a new hard disk that hasn't been partitioned yet, you'll get a warning message. Read it, and if you want to continue, press C.

6. Read and accept the licensing agreement and press F8 if you accept it.

7. Select or create the partition on which you will install W2K. Depending upon your existing disk configuration choose one of the following:

If the hard disk is not yet partitioned, you can create and size the partition on which you will install Windows 2000. Press C.

If the hard disk is new and you want to create a partition that will span the entire hard disk's size - press Enter.

Other optionsL

If the hard disk is already partitioned, but has enough unpartitioned disk space, you can create an additional partition in the unpartitioned space.

If the hard disk already has a partition that is large enough, you can install Windows 2000 on that partition. If the partition has an existing operating system, you will overwrite that operating system if you accept the default installation path. However, files other than the operating system files, such as program files and data files, will not be overwritten.

If the hard disk has an existing partition, you can delete it to create more unpartitioned space for the new partition. Deleting an existing partition erases all data on that partition.

If you select a new partition during Setup, create and size only the partition on which you will install Windows 2000. After installation, use Disk Management to partition the remaining space on the hard disk.

8. Select a file system for the installation partition. After you create the partition on which you will install W2K, you can use Setup to select the file system with which to format the partition. W2K supports the NTFS file system in addition to the file allocation table (FAT) and FAT32 file systems. Windows Server 2003, Windows XP Professional, Windows 2000, and Windows NT are the only Microsoft operating systems that you can use to gain access to data on a local hard disk that is formatted with NTFS. If you plan to gain access to files that are on a local W2K partition with the Microsoft Windows 95 or Windows 98 operating systems, you should format the partition with a FAT or FAT32 file system. We will use NTFS.

9. Setup will then begin copying necessary files from the installation point (CD, local I386 or network share).

10. Note: If you began the installation process from an MS-DOS floppy, make sure you have and run SMARTDRV from the floppy, otherwise the copying process will probably last more than an hour, perhaps even more. With SMARTDRV (or if setup was run by booting from CD) the copying will probably last a few minutes, no more than 5 max.

11. The computer will restart in graphical mode, and the installation will continue.

Step #4: The GUI-based portion of the Setup program

The setup process reboots and loads a GUI mode phase.

It will then begin to load device drivers based upon what it finds on your computer. You don't need to do anything at this stage.

If your computer stops responding during this phase (the progress bar is stuck almost half-way, and there is no disk activity) - shut down your computer and begin removing hardware such as PCI and ISA cards. If it works for you then later try to figure out how to make that specific piece of hardware work (it's probably not in the HCL).

Click Customize to change regional settings, if necessary.

Current System Locale - Affects how programs display dates, times, currency, and numbers. Choose the locale that matches your location, for example, French (Canada).

Current Keyboard Layout - Accommodates the special characters and symbols used in different languages. Your keyboard layout determines which characters appear when you press keys on the keyboard.

If you don't need to make any changes just press Next.

If you do need to make changes press Customize and add your System Locale etc.

Note for Hebrew users: In W2K it is NOT SAFE to install Hebrew language support at this phase!!! Trust me, do it later. If you don't listen to me, good chances are that you'll get ???? fonts in some Office applications such as Outlook and others.

Read the Install Hebrew on Windows 2000 page for more info.

Type your name and organization.

Type the product key.

Enter the appropriate license type and number of purchased licenses.

Type the computer name and a password for the local Administrator account. The local Administrator account resides in the SAM of the computer, not in Active Directory. If you will be installing in a domain, you need either a pre-assigned computer name for which a domain account has been created, or the right to create a computer account within the domain.

Choose which components to install or remove from the system.

Select the date, time, and time zone settings.

Setup will now install the networking components.

After a few seconds you will receive the Networking Settings window. BTW, if you have a NIC that is not in the HCL (see the What's the HCL? page) and W2K cannot detect it, or if you don't have a NIC at all, setup will skip this step and you will immediately go to the final phase of the setup process.

Press Next to accept the Typical settings option if you have one of the following situations:

You have a functional DHCP on your network.

You have a computer running Internet Connection Sharing (ICS).

You're in a workgroup environment and do not plan to have any other servers or Active Directory at all, and all other workgroup members are configured in the same manner.

Otherwise select Custom Settings and press Next to customize your network settings.

9. Highlight the TCP/IP selection and press Properties.

In the General tab enter the required information. You must specify the IP address of the computer, and if you don't know what the Subnet Mask entry should be - you can simply place your mouse pointer over the empty area in the Subnet Mask box and click it. The OS will automatically select the value it thinks is good for the IP address you provided.

10. In the Workgroup or Domain window enter the name of your workgroup or domain.

A workgroup is a small group of computers on a network that enables users to work together and does not support centralized administration.

A domain is a logical grouping of computers on a network that has a central security database for storing security information. Centralized security and administration are important for computers in a domain because they enable an administrator to easily manage computers that are geographically distant from each other. A domain is administered as a unit with common rules and procedures. Each domain has a unique name, and each computer within a domain has a unique name.

If you're a stand-alone computer, or if you don't know what to enter, or if you don't have the sufficient rights to join a domain - leave the default entry selected and press Next.

If you want to join a domain (NT 4.0 domain of W2K/2003 Active Directory domain) enter the domain's name in the "Yes, make this computer a member of the following domain" box.

To successfully join a domain you need the following:

The person performing the installation must have a user account in Active Directory. This account does not need to be the domain Administrator account.

and

The computer must have an existing computer account in the Active Directory database of the domain that the computer is joining, and the computer must be named exactly as its domain account is named.

The person performing the installation must have appropriate permission to create a domain account for the computer during installation.

Also, you need to have connectivity to the domain's domain controllers (only to the PDC if on an NT 4.0 domain) and a fully functional DNS server (only in AD domains). Read the Joining a Domain in Windows XP Pro and Requirements when Joining a Domain pages for more on this issue.

Note: Providing a wrong username or password will cause this phase to fail.

11. Next the setup process will finish copying files and configuring the setup. You do not need to do anything.

Enter the Active Directory domain name (in the form of xxx.yyy, for example: DPETRI.NET) or the NetBIOS name of the NT 4.0 domain (in the form of xxx, for example: DPETRI). Press Next.

Note: If you provide a wrong domain name or do not have the correct connectivity to the domain's DNS server you will get an error message.

A username/password window will appear. Enter the name and password of the domain's administrator (or your own if you're the administrator on the target domain).

12. After the copying and configuring phase is finished, if Windows Server 2003 finds that you have a badly configured screen resolution it will advise you to change it and ask you if you see the new settings right.

13. Setup finishes and displays the finish window. Unfortunately, you must press Finish in order to reboot..

14. Windows 2000 reboots and you should get the CTRL-ALT-DEL window.

15. That's it! you're done!

2009-09-17T02:30:00.000-07:00

Install Windows XP

Part 1: Begin the installation

Insert the Windows XP CD into your computer and restart your computer.

If prompted to start from the CD, press SPACEBAR. If you miss the prompt (it only appears for a few seconds), restart your computer to try again.

3.	Windows XP Setup begins. During this portion of setup, your mouse will not work, so you must use the keyboard. On the Welcome to Setup page, press ENTER.

4.	On the Windows XP Licensing Agreement page, read the licensing agreement. Press the PAGE DOWN key to scroll to the bottom of the agreement. Then press F8.

This page enables you to select the hard disk drive on which Windows XP will be installed. Once you complete this step, all data on your hard disk drive will be removed and cannot be recovered. It is extremely important that you have a recent backup copy of your files before continuing. When you have a backup copy, press D, and then press L when prompted. This deletes your existing data.

Press ENTER to select Unpartitioned space, which appears by default.

7.	Press ENTER again to select Format the partition using the NTFS file system, which appears by default.

8.	Windows XP erases your hard disk drive using a process called formatting and then copies the setup files. You can leave your computer and return in 20 to 30 minutes. Part 2: Continue the installation

Windows XP restarts and then continues with the installation process. From this point forward, you can use your mouse. Eventually, the Regional and Language Options page appears. Click Next to accept the default settings. If you are multilingual or prefer a language other than English, you can change language settings after setup is complete.

10.	On the Personalize Your Software page, type your name and your organization name. Some programs use this information to automatically fill in your name when required. Then, click Next.

11.	On the Your Product Key page, type your product key as it appears on your Windows XP CD case. The product key is unique for every Windows XP installation. Then, click Next.

12.

On the Computer Name and Administrator Password page, in the Computer name box, type a name that uniquely identifies your computer in your house, such as FAMILYROOM or TOMS. You cannot use spaces or punctuation. If you connect your computer to a network, you will use this computer name to find shared files and printers. Type a strong password that you can remember in the Administrator password box, and then retype it in the Confirm password box. Write the password down and store it in a secure place. Click Next.

13.	On the Date and Time Settings page, set your computer’s clock. Then, click the Time Zone down arrow, and select your time zone. Click Next.

14.	Windows XP will spend about a minute configuring your computer. On the Networking Settings page, click Next.

15.	On the Workgroup or Computer Domain page, click Next.

Part 3: Complete the installation

16.	Windows XP will spend 20 or 30 minutes configuring your computer and will automatically restart when finished. When the Display Settings dialog appears, click OK.

17.	When the Monitor Settings dialog box appears, click OK.

18.	The final stage of setup begins. On the Welcome to Microsoft Windows page, click Next.

19.	On the Help protect your PC page, click Help protect my PC by turning on Automatic Updates now. Then, click Next.

20.	Windows XP will then check if you are connected to the Internet:

If you are connected to the Internet, select the choice that describes your network connection on the Will this computer connect to the Internet directly, or through a network? page. If you’re not sure, accept the default selection, and click Next.
If you use dial-up Internet access, or if Windows XP cannot connect to the Internet, you can connect to the Internet after setup is complete. On the How will this computer connect to the Internet? page, click Skip.

21.

Windows XP Setup displays the Ready to activate Windows? page. If you are connected to the Internet, click Yes, and then click Next. If you are not yet connected to the Internet, click No, click Next, and then skip to step 24. After setup is complete, Windows XP will automatically remind you to activate and register your copy of Windows XP.

22.	On the Ready to register with Microsoft? page, click Yes, and then click Next.

23.	On the Collecting Registration Information page, complete the form. Then, click Next.

24.

On the Who will use this computer? page, type the name of each person who will use the computer. You can use first names only, nicknames, or full names. Then click Next. To add users after setup is complete or to specify a password to keep your account private, read Create and customize user accounts.

25.	On the Thank you! page, click Finish.

Resource allocation graph

2009-08-27T02:49:00.000-07:00

Resource allocation graph

Deadlock can be described through a resource allocation graph.

The RAG consists of a set of vertices P={P1,P2 ,…,Pn} of processes and R={R1,R2,…,Rm} of resources.

A directed edge from a processes to a resource, Pi->Rj, implies that Pihas requested Rj.

A directed edge from a resource to a process, Rj->Pi, implies that Rjhas been allocated by Pi.

If the graph has no cycles, deadlock cannot exist. If the graphhas a cycle, deadlock may exist.

(a) The vertices of our graph are processes, represented by circles,

(b)resources, represented by squares, which may have a number of “dots” inside to indicatemultiple equivalent instances of a resource

(c) Edges from a process to a resource indicate a request by that process for an instance of that re-source.(d) arc (rj,pi) means process i has resource j

(e)Edges from a resource to a process indicate that the resource has been granted to that process.

Resource Allocation Graph

2009-08-27T01:48:00.000-07:00

Resource Allocation Graph

> If the graph does not contain a cycle,then no deadlock exists

> If the graph does not contain a knot,then a deadlock does not exist

> If there is a cycle:

>> If there is only one instance per resource type then there is a deadlock.

>> If there is more than one instance for some resource type, there may or may not be a deadlock.

> There are no cycles in this graph, so we are sure that there is no deadlock. There are two unfulﬁlledrequests, P1’s request for R1, and P2’s request for R3, but we are sure things can continue. SinceP3 isn’t waiting for anything, it will eventually release R3. P2 can then do its thing, allowing it torelease R1, which allows P1 to do its thing. But what if P3 requests an instance of R2?

Resource Allocation Graph With A Deadlock

> If the graph does contain a cycle,then a deadlock does exist

> If the graph does contain a knot (and acycle), then a deadlock does exist

> A cycle is a necessary and sufficient condition for deadlock.

> Deadlock! P3 cannot continue until it acquires an R2. But we know that P2 can’t continue until itgets an R3, which isn’t going to happen until P3 can go. But P1 is waiting for an R1, which isn’tavailable until P2 can go... We have a problem. No process can continue.

Resource Allocation Graph With A Cycle But No Deadlock

> If there is a cycle in the graph, and each resource has more than one instance, there may or may not be deadlock. (A cycle may be broken if some process outside the cycle has a resource instance that can break the cycle.)

> Here, there is a cycle, but P2 and P4 are not waiting for anything. That means that eventually theywill free their resources, and the other processes can get what they need.If there is a single instance of each resource, a cycle in the resource allocation graph means wehave deadlock. When there are multiple instances, it only means there is a possibility of deadlock.

Unsafe State In Resource-Allocation Graph

> There is no deadlock yet, since there’s a chance that P1 will not need R2 before completing,thereby freeing up R1 for P2. But the state is not safe, since we cannot guarantee a safe sequence.It’s possible that P1 will need R2 before it releases R1, and deadlock would follow.

> An unsafe state does not guarantee deadlock, as even if no such sequence exists, it’s possible thatone or more processes will not request the maximum allocation of a resource. So a process couldcomplete and free resources, but maybe not.

Resource-Allocation Graph For Deadlock Avoidance

> Here, P1 has been granted R1 and has a claim edge indicating that it may also need R2. P2 iscurrently requesting R1 and also may need R2.This is a safe state, as P1, P2 is a safe sequence.

2009-08-20T04:01:00.000-07:00

Deadlock Characterization

Deadlock can arise if four conditions hold simultaneously:

> Mutual exclusion: only one process at a time can use a resource

> Hold and wait: a process holding at least one resource is waiting to acquire additional resources held by other processes

> No preemption: a resource can be released only voluntarily bythe process holding it, after that process has completed its task

> Circular wait: there exists a set {P0, P1, …, Pn, P0} of waiting processes such that

– P0 is waiting for a resource that is held by P1,

– P1 is waiting for a resource that is held by P2,

– …,

– Pn–1 is waiting for a resource that is held by Pn,

– and Pn is waiting for a resource that is held by P0.

2009-08-20T03:58:00.000-07:00

Methods for handling deadlocks

>> Ignore the problem and pretend that deadlocks would never occur

>> Ensure that the system will never enter a deadlock state

>> Allow the system to enter a deadlock state and then detect/recover

2009-08-20T03:51:00.000-07:00

Deadlock Prevention

>> Difference from avoidance is that here, the system itself is build in such a way that there are no deadlocks.

>> Make sure at least one of the 4 deadlock conditions is never satisfied.

>> This may however be even more conservative than deadlock avoidance strategy.

> Attacking Mutual condition

> never grant exclusive access. but this may not be possible for several resources.

> we always want to minimize the number ofnon-sharable resources, but it is notusually possible to eliminate all of them.

> Attacking pre-emption

> not something you want to do.

> cannot usually take a resource away froma process.

> Attacking hold and wait condition

> make a process hold at the most 1 resource at a time.

> make all the requests at the beginning. All or nothing policy. If you feel, retry. eg. 2-phase locking

> require each process to request and beallocated all resources before it beginsexecuting

> before requesting a new resource releaseall locks on other resources and reacquire.

> Problems: low resource utilization,starvation

> Attacking circular wait

> Order all the resources.

> Make sure that the requests are issued in the correct order so that there are no cycles present in the resource graph.

> This is where most of the effort ofdeadlock prevention is focused.

> Design a hierarchy of lock acquisition suchthat there are no cycles.

> A great idea in theory, but difficult toimplement in practice because theunderlying code does not usually follow anacyclic hierarchy.

2009-08-20T03:48:00.000-07:00

Deadlock Detection

>> Diffusing computation: Dijkstra/Scholten algorithm

>> Simple signaling protocol detects deadlock

>> Does not detect partial (local) deadlocks

2009-08-20T03:46:00.000-07:00

Deadlock Recovery

>> Smallest time stamp event safe to process

>> Others may also be safe (requires additional work to determine this)

2009-08-13T04:01:00.000-07:00

Multiprocessor Scheduling

>> is an NP-Complete optimization problem.

>> Given a set of runnable threads, and a set of CPUs, assign threads to CPUs

>> Same considerations as uniprocessorscheduling

(Fairness, efficiency, throughput, response time…)

>> But also new considerations:

=> Load balancing

=> Processor affinity

>> Will consider only shared memory multiprocessor

Central queue – queue can be a bottleneck

Distributed queue – load balancing between queue

Real Time Scheduling

>> Real time means that correctness of result depends on both functional correctness and time that the result is delivered

Thread Scheduling

>> responsible for sharing the available CPUs out between the various threads

>> Each thread has its own set of scheduling parameters

>> These parameters can be set using the thread attributes object before the thread's creation. They can also be dynamically set during the thread's execution

thread scheduling criteria:

=> a priority, or in fact usually multiple "priority" settings that we'll discuss below;

=> a quantum, or number of allocated timeslices of CPU, which essentially determines the amount of CPU time a thread is allotted before it is forced to yield the CPU to another thread of the same or lower priority

=> a state, notably "runnable" vs "waiting";

=> metrics about the behaviour of threads, such as recent CPU usage or the time since it last ran (i.e. had a share of CPU), or the fact that it has "just received an event it was waiting for".

2009-08-10T18:59:00.000-07:00

Windows XP thread

Implements the one-to-one mapping

Each thread contains:

> A thread id

> Register set

> Separate user and kernel stacks

> Private data storage are

The register set, stacks, and private storage area are known as the context of the threads

The primary data structure of a thread include:

> ETHREAD (executive thread block)

> KTHRED (kernel thread block)

> TEB (thread environment block)

Java Thread

Java thread are managed by the JVM

Java thread may created by:

> Extending thread class

> Implementing the Runnable inteface

In Java, each thread is represented by an object of class java.lang.Thread, which handles the necessary bookkeeping and provides methods for controlling the thread

Linux Thread

Linux refers to them as tasks rather than threads

Thread creation is done through clone() system call

clone() allows a child to share the address space of the parent task(process)

2009-08-10T05:54:00.000-07:00

Different cpu scheduling algorithms

First Come, First Served (FCFS)

>> Non-preemptive
>> Treats ready queue as FIFO.
>> Simple, but typically long/varying waiting time.

Shortest Job First (SJF)

>> Give CPU to the process with the shortest next burst
>> If equal, use FCFS
>> Better name: shortest next cpu burst first

Round-Robin (RR)

>> FCFS with Preemption
>> Time quantum (or time slice)
>> Ready Queue treated as circular queue

Shortest Remaining Time (SRT)
>> Preemptive version of shortest process next policy
>> Must estimate processing time

2009-07-30T03:52:00.000-07:00

Thread library

>> allows concurrent programming in Objective Caml

>> It provides multiple threads of control (also called lightweight processes) that execute concurrently in the same memory space

>> implemented by time-sharing on a single processor

2009-07-30T03:43:00.000-07:00

Thread

>> is a path of execution through a program

>> is short for a thread of execution

>> are a way for a program to fork (or split) itself into two or more simultaneously (or pseudo-simultaneously) running tasks

Single threaded process

>> have one path of execution

>> can perform only one task at a time, and have to finish each task in sequence before they can start another

>> when the OS does not recognize the concept of thread

Multi threaded process

>> multi-threaded programs have two or more paths of execution

>> when the OS supports multiple threads of execution within a single process

2009-07-30T03:33:00.000-07:00

Benefits of multi-threaded programming

> Responsiveness

> Resource Sharing

> Economy

> Utilization of MP Architectures

2009-07-30T03:31:00.000-07:00

User thread

>> Thread management done by user-level threads library

>> includes a set of registers and a stack, and shares the entire address space with the other threads in the enclosing process

>> is handled entirely in user code, usually by a special library that provides at least start, swap and suspend calls

2009-07-30T03:28:00.001-07:00

Kernel threads

==> Supported by the Kernel

==> Kernel can run them on multiple processors in parallel

2009-07-30T03:20:00.000-07:00

Multithreading Models

Many-to-one models

==>> Many user-level threads mapped to single kernel thread

One-to-one models

==> Each user-level thread maps to kernel thread

Many-to-many models

==> Allows many user level threads to be mapped to many kernel threads

==> Allows the operating system to create a sufficient number of kernel threads

2009-07-30T02:14:00.000-07:00

Indirect communication

Synchronozation

-> refers to one of two distinct but related concepts: synchronization of processes, and synchronization of data. Process synchronization refers to the idea that multiple processes are to join up or handshake at a certain point, so as to reach an agreement or commit to a certain sequence of action.

>>Blocking send

==>> A blocking send can be used with a non-blocking receive, and vice-versa, e.g.,

>> Nonblocking send

==>> can use any mode - synchronous, buffered, standard or ready

==>> returns as soon as possible, that is, as soon as it has posted the send. The buffer might not be free for reuse.

>> Blocking receive

==>> returns as soon as the data is ready in the receive buffer.

>> Nonblocking receive

==>> returns as soon as possible, that is, either with a flag that the data has not arrived yet or with the data in the receive buffer.

Buffering

-> A device or area used to store data temporarily.

-> To hold or collect (data) in a buffer.

>> Zero capacity

>> Bounded Capacity

==>> The bounded buffer is a classic concurrent programming component exhibiting asynchronous task interactions.The concept is that of a buffer of a fixed size that is accessed by multiple tasks, some inserting items and some removing them, concurrently and asynchronously. Hence the buffer implementation must be protected against race conditions in which the tasks access the implementation in an interleaved manner and thereby corrupt the representation. In addition to this “mutually exclusive access”, the buffer also requires “condition synchronization”, in which callers are kept waiting until the requested buffer has the necessary state. For example, a task cannot remove an item from a buffer when the buffer is empty. Likewise, an item cannot be put into a buffer when the buffer is full.

Producer - Consumer Example

Producer ==> generates an integer between 0 and 9 (inclusive), then stores it in a CubbyHole object. To make the synchronization problem more interesting, the Producer sleeps for a random amount of time between 0 and 100 milliseconds before repeating the number-generating cycle.
Consumer ==> consumes all integers from the CubbyHole (the exact same object into which the Producer put the integers in the first place) as quickly as they become available.

=> The Producer and Consumer examples share data through a common CubbyHole object. Although, ideally, Consumer will get each value produced once and only once, neither Producer nor Consumer makes any effort whatsoever to ensure that this happens. The synchronization between these two threads occurs at a lower level within the get and put methods of the CubbyHole object. Assume for a moment, however, that the two threads make no arrangements for synchronization; let's discuss the potential problems that might arise from this.

=> One problem arises when the Producer is quicker than the Consumer and generates two numbers before the Consumer has a chance to consume the first one. In this situation, the Consumer misses a number. Part of the output might look like the following figure.

=> Another problem might arise when the Consumer is quicker than the Producer and consumes the same value twice. In this situation, the Consumer might produce the output shown in the following figure.

==> Either way, the result is wrong because the Consumer should get each integer produced by the Producer exactly once. A problem like this is called a race condition. A race condition is a situation in which two or more threads or processes are reading or writing some shared data, and the final result depends on the timing of how the threads are scheduled. Race conditions can lead to unpredictable results and subtle program bugs. Race conditions in the producer-consumer example are prevented by having storage of a new integer in the CubbyHole by the Producer synchronized with retrieval of an integer from the CubbyHole by the Consumer. The activities of the Producer and the Consumer must be synchronized in two ways.

==> First, the two threads must not simultaneously access the CubbyHole. A thread can prevent this from happening by locking an object. When an object is locked by one thread and another thread tries to call a synchronized method on the same object, the second thread will be blocked until the object is unlocked.

==> Second, the two threads must do some simple coordination. That is, the Producer must have a way to indicate to the Consumer that the value is ready, and the Consumer must have a way to indicate that the value has been retrieved. The Object class provides a collection of methods — wait, notify, and notifyAll — to help threads wait for a condition and to notify other threads when that condition changes.

2009-07-16T03:26:00.000-07:00

Interprocess Communication (IPC)

Mechanism for processes to communicate and to synchronize their actions.

Message system = processes communicate with each other without resorting to shared variables.

IPC facility provides two operations:

==> send(message) –message size fixed or variable

==> receive(message)

If P and Q wish to communicate, they need to:

=>> establish a communication link between them

=>> exchange messages via send/receiven

Implementation of communication link

=>> physical (e.g., shared memory, hardware bus) considered later

=>> logical (e.g., logical properties) now

2009-07-16T03:24:00.000-07:00

Cooperating Processes

Independent process cannot affect or be affected by the execution of another process.Cooperating process can affect or be affected by the execution of another process

Advantages of process cooperation

--> Information sharing

--> Computation speed-up

--> ModularityF Convenience

2009-07-16T02:31:00.000-07:00

Operations on Processes

a. Process Creation

Parent process creates children processes, which, in turn create other processes, forming a tree of processes.

Resource sharing

--> Parent and children share all resources.

--> Children share subset of parent’s resources.

--> Parent and child share no resources.

Execution

--> Parent and children execute concurrently.

--> Parent waits until children terminate.

Address space

--> Child duplicate of parent.

--> Child has a program loaded into it.

b. Process Termination

Process executes last statement and asks the operating system to delete it (exit).

--> Output data from child to parent (via wait).

--> Process’ resources are deallocated by operating system.

Parent may terminate execution of children processes (abort).

--> Child has exceeded allocated resources.

--> Task assigned to child is no longer required.

--> Parent is exiting.

=> Operating system does not allow child to continue if its parent terminates.

=> Cascading termination.

2009-07-16T02:27:00.000-07:00

Process Scheduling

a. Process Scheduling Queues

Job queue = set of all processes in the system.

Ready queue = set of all processes residing in main memory, ready and waiting to execute.

Device queues = set of processes waiting for an I/O device.

Processes migrate between the various queues.

b. Schedulers

Long-term scheduler (or job scheduler) – selects which processes should be brought into the ready queue. Long-term scheduler is invoked very infrequently (seconds, minutes) => (may be slow).

Short-term scheduler (or CPU scheduler) – selects which process should be executed next and allocates CPU. Short-term scheduler is invoked very frequently (milliseconds) => (must be fast).

The long-term scheduler controls the degree of multiprogramming.

Processes can be described as either:

>> I/O-bound process – spends more time doing I/O than computations, many short CPU bursts.

>> CPU-bound process – spends more time doing computations; few very long CPU bursts.

c. Context Switch

When CPU switches to another process, the system must save the state of the old process and load the saved state for the new process.

Context-switch time is overhead; the system does no useful work while switching.

Time dependent on hardware support.

2009-07-16T01:45:00.000-07:00

The Concept of Process

An operating system executes a variety of programs:

Batch system ==> jobs

Time-shared systems ==> user programs or task

Textbook uses the terms job and process almost interchangeably.
Process – a program in execution; process execution must progress in sequential fashion.

A process includes:

= program

= stack

= data section

a. Process State

As a process executes, it changes state
-- new: The process is being created.

-- running: Instructions are being executed.

-- waiting: The process is waiting for some event to occur.

-- ready: The process is waiting to be assigned to a processor

-- terminated: The process has finished execution.

b. Process Control Block (PCB)

Information associated with each process.

-- Process ID

-- Process staten

-- Program countern

-- CPU registersn CPU scheduling informationn

-- Memory-management informationn

-- Accounting informationn

-- I/O status information

c. Threads

==> results from a fork of a computer program into two or more concurrently running tasks. The implementation of threads and processes differs from one operating system to another, but in most cases, a thread is contained inside a process. Multiple threads can exist within the same process and share resources such as memory, while different processes do not share these resources.

Quiz #3

2009-07-09T04:02:00.000-07:00

1. What are the major activities of the OS with regards to process management?

===>> Process creation
===>> Process suspension and resumption
===>> Provision of mechanism for:

=> process synchronization
=> process communication
=> deadlock handling

2. What are the major activities of the OS with regards to memory management?

===>> Keep track off with parts of memory are currently being used and by whom
===>> Decide wich processor to load when memory space becomes available
===>> Allocate and deallocate memory space as needed

3. What are the major activities of the OS with regards to secondary-storage management?

===>> Free space management
===>> Storage allocation
===>> Disk scheduling

4. What are the major activities of the OS with regards to file management?

===>> File creation and deletion
===>> Directory creation and deletion
===>> Support of primitives for manipulating files and directories
===>> Mapping files onto secondary storage device
===>> File backup on stable(non-volatile) storage media

5. What are the purpose of command interpreter?

===>> It reads commands from the user or from a ﬁle of commandsand executes them, usually by turning them into one or more systemcalls. It is usually not part of the kernel since the command interpreteris subject to changes.

2009-07-07T03:41:00.000-07:00

System Generation

---- (computer science) A process that creates a particular and uniquely specified operating system; it combines user-specified options and parameters with manufacturer-supplied general-purpose or nonspecialized program subsections to produce an operating system (or other complex software) of the desired form and capacity. Abbreviated sysgen.

2009-07-07T02:58:00.000-07:00

Virtual Machine

----a computer which is emulated by a program.NOTES:„ There is no reason why the virtual machinecannot have the architecture of a real computer.„ The emulation program can run on a real computer with the same architecture as the virtual machine being emulated.

Implementation:

Virtual machines are usually written in “portable” (in the sense that compilers for most architectures already exists) programming languages such as C or C++.
For performance critical components assembly language can be used.
Some VMs (Lisp, Forth, Smalltalk) are largely written in the language itself.
Many VMs are written specifically for gcc, for reasons that will become clear in later slides.

2009-07-07T02:56:00.000-07:00

System Boot

Operating system must be made available to hardware so hardware can start it
-- Small piece of code – bootstrap loader, locates the kernel, loads it into memory, and starts it
-- Sometimes two-step process where boot block at fixed location loads bootstrap loader -- When power initialized on system, execution starts at a fixed memory location
--- >> Firmware used to hold initial boot code

2009-07-02T04:01:00.000-07:00

System Structure

Simple Structure

– any part of the system may use the functionality of the rest of
the system
– MS-DOS (user programs can call low level I/O routines)

Layered Approach

– layer n can only see the functionality that layer n-1 exports
– provides good abstraction from the lower level details
• new hardware can be added if it provides the interface required of a particular layer
– system call interface is an example of layering
– can be slow if there are too many layers

2009-07-02T03:48:00.000-07:00

System Calls
Provide the interface between application programs and the kernel
Are like procedure calls
– take parameters
– calling routine waits for response
Permit application programs to access protectedresources

Process Control
– create/terminate a process (including self)

File Management
– open, create
– read, write
– close, delete
– get or set file attributes
Also referred to as simply a file system or filesystem. The system that an operating system or program uses to organize and keep track of files. For example, a hierarchical file system is one that uses directories to organize files into a tree structure.
Although the operating system provides its own file management system, you can buy separate file management systems. These systems interact smoothly with the operating system but provide more features, such as improved backup procedures and stricter file protection.

Device Management
Device Management is a set of technologies, protocols and standards used to allow the remote management of mobile devices, often involving updates of firmware over the air (FOTA). The network operator, handset OEM or in some cases even the end-user (usually via a web portal) can use Device Management, also known as Mobile Device Management, or MDM, to update the handset firmware/OS, install applications and fix bugs, all over the air. Thus, large numbers of devices can be managed with single commands and the end-user is freed from the requirement to take the phone to a shop or service center to refresh or update.

Information Maintenance
– get time
– set system data (OS parameters)
– get process information (id, time used)

2009-07-02T03:46:00.000-07:00

Operating System Services

Program execution – system capability to load a program into memory and to run it.
I/O operations – since user programs cannot execute I/O operations directly, the operating system must provide some means to perform I/O.
File-system manipulation – program capability to read, write, create, and delete files.
Communications – exchange of information between processes executing either on the same computer or on different systems tied together by a network. Implemented via shared memory or message passing.
Error detection – ensure correct computing by detecting errors in the CPU and memory hardware, in I/O devices, or in user programs.

2009-07-02T03:11:00.000-07:00

System Components

Process Management

A process is a program in execution. A process needs certain resources, including CPU time, memory, files, and I/O devices, to accomplish its task. The operating system is responsible for the following activities in connection with process management.

Process creation and deletion.
process suspension and resumption.
Provision of mechanisms for:

a. process synchronization
b. process communication

Main-Memory Management

Memory is a large array of words or bytes, each with its own address. It is a repository of quickly accessible data shared by the CPU and I/O devices. Main memory is a volatile storage device. It loses its contents in the case of system failure. The operating system is responsible for the following activities in connections 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.

File Management

A file is a collection of related information defined by its creator. Commonly, files represent programs (both source and object forms) and data.

The operating system 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.

I/O System Management

The I/O system consists of:

A buffer-caching system
A general device-driver interface
Drivers for specific hardware devices

Secondary-Storage Management

Since main memory (primary storage) is volatile and too small to accommodate all data and programs permanently, the computer system must provide secondary storage to back up main memory. Most modern computer systems use disks as the principle on-line storage medium, for both programs and data.

The operating system is responsible for the following activities in connection with disk management:

Free space management
Storage allocation
Disk scheduling

Networking (Distributed Systems)

A distributed system is a collection processors that do not share memory or a clock. Each processor has its own local memory. The processors in the system are connected through a communication network. Communication takes place using a protocol. A distributed system provides user access to various system resources.

Access to a shared resource allows:

Computation speed-up
Increased data availability
Enhanced reliability

Protection System

Protection refers to a mechanism for controlling access by programs, processes, or users to both system and user resources.

The protection mechanism must:

distinguish between authorized and unauthorized usage.
specify the controls to be imposed.
provide a means of enforcement.

Command-Interpreter System

Many commands are given to the operating system by control statements which deal with:

process creation and management
I/O handling
secondary-storage management
main-memory management
file-system access
protection
networking

The program that reads and interprets control statements is called variously:

command-line interpreter
shell (in UNIX)

Its function is to get and execute the next command statement.

2009-06-25T03:27:00.000-07:00

5. Device status table

2009-06-25T02:48:00.000-07:00

Hardware Protection

Hardware protection can accomplish various things, including: write protection for hard disk drives, memory protection, monitoring and trapping unauthorized system calls, etc.

Dual-Mode Operation

Sharing system resources requires operating system to ensurethat an incorrect program cannot cause other programs toexecute incorrectly.

Provide hardware support to differentiate between at least twomodes of operations.

1. User mode – execution done on behalf of a user.

2. Monitor mode (also supervisor mode or system mode) –execution done on behalf of operating system.

I/O Protection

All I/O instructions are privileged instructions.

Must ensure that a user program could never gain control ofthe computer in monitor mode (i.e., a user program that, aspart of its execution, stores a new address in the interruptvector).

Memory Protection

Must provide memory protection at least for the interrupt vectorand the interrupt service routines.

In order to have memory protection, add two registers thatdetermine the range of legal addresses a program may access:

– base register – holds the smallest legal physical memoryaddress.

– limit register – contains the size of the range.

Memory outside the deﬁned range is protected.

CPU Protection

To prevent a user programs gets stuck in infinite loop and never returning back to the os.

2009-06-25T02:24:00.000-07:00

Storage Hierarchy

The hierarchical arrangement of storage in current computer architectures is called the memory hierarchy. It is designed to take advantage of memory locality in computer programs. Each level of the hierarchy has the properties of higher bandwidth, smaller size, and lower latency than lower levels. Most modern CPUs are so fast that for most program workloads, the locality of reference of memory accesses and the efficiency of the caching and memory transfer between different levels of the hierarchy are the practical limitation on processing speed. As a result, the CPU spends much of its time idling, waiting for memory I/O to complete. This is sometimes called the space cost, as a larger memory object is more likely to overflow a small/fast level and require use of a larger/slower level.

Caching

In computer science, a cache (pronounced /kæʃ/) is a collection of data duplicating original values stored elsewhere or computed earlier, where the original data is expensive to fetch (owing to longer access time) or to compute, compared to the cost of reading the cache. In other words, a cache is a temporary storage area where frequently accessed data can be stored for rapid access. Once the data is stored in the cache, it can be used in the future by accessing the cached copy rather than re-fetching or recomputing the original data.
A cache has proven to be extremely effective in many areas of computing because access patterns in typical computer applications have locality of reference. There are several kinds of locality, but this article primarily deals with data that are accessed close together in time (temporal locality). The data might or might not be located physically close to each other (spatial locality).

Coherency

In computing, cache coherence (also cache coherency) refers to the integrity of data stored in local caches of a shared resource. Cache coherence is a special case of memory coherence.
When clients in a system maintain caches of a common memory resource, problems may arise with inconsistent data. This is particularly true of CPUs in a multiprocessing system. Referring to the "Multiple Caches of Shared Resource" figure, if the top client has a copy of a memory block from a previous read and the bottom client changes that memory block, the top client could be left with an invalid cache of memory without any notification of the change. Cache coherence is intended to manage such conflicts and maintain consistency between cache and memory.

Consistency

In computer science, in a distributed system such as a distributed shared memory system or a distributed data store such as a database, filesystem, web caching or optimistic replication systems, there are a number of possible data consistency models. The system supports a given model if operations on memory follow specific rules. The data consistency model specifies a contract between programmer and system, wherein the system guarantees that if the programmer follows the rules, memory will be consistent and the results of memory operations will be predictable.

2009-06-25T01:53:00.000-07:00

Storage Structure

Main Memory

The main memory of the computer is also known as RAM, standing for Random Access Memory. It is constructed from integrated circuits and needs to have electrical power in order to maintain its information. When power is lost, the information is lost too! It can be directly accessed by the CPU. The access time to read or write any particular byte are independent of whereabouts in the memory that byte is, and currently is approximately 50 nanoseconds (a thousand millionth of a second). This is broadly comparable with the speed at which the CPU will need to access data. Main memory is expensive compared to external memory so it has limited capacity. The capacity available for a given price is increasing all the time. For example many home Personal Computers now have a capacity of 16 megabytes (million bytes), while 64 megabytes is commonplace on commercial workstations. The CPU will normally transfer data to and from the main memory in groups of two, four or eight bytes, even if the operation it is undertaking only requires a single byte.

Magnetic Disk

A memory device, such as a floppy disk, a hard disk, or a removable cartridge, that is covered with a magnetic coating on which digital information is stored in the form of microscopically small, magnetized needles.

a. Moving Head Disk Mechanism

Magnetic Tape

A plastic tape coated with iron oxide for use in magnetic recording.

A device for storing information, in which signals are recorded by lining up small bits of magnetic materials in the coating on the tape. Ordi nary tape recorders use magnetic tape.

A continuous, flexible, recording medium whose basic material is impregnated or coated with a magnetic-sensitive material ready to accept data in the form of magnetically polarized spots.

A tape or ribbon of any material impregnated or coated with magnetic or other material on which information may be placed in the form of magnetically polarized spots.

2009-06-24T18:08:00.000-07:00

1. Bootstrap program

In computing, bootstrapping (from an old expression "to pull oneself up by one's bootstraps") is a technique by which a simple computer program activates a more complicated system of programs. In the start up process of a computer system, a small program such as BIOS, initializes and tests that hardware, peripherals and external memory devices are connected, then loads a program from one of them and passes control to it, thus allowing loading of larger programs, such as an operating system.

A different use of the term bootstrapping is to use a compiler to compile itself, by first writing a small part of a compiler of a new programming language in an existing language to compile more programs of the new compiler written in the new language. This solves the "chicken and egg" causality dilemma.

Booting

Bootstrapping was shortened to booting, or the process of starting up any computer, which is the most common meaning for non-technical computer users. The verb "boot" is similarly derived.

A "bootstrap" most commonly refers to the simple program itself that actually begins the initialization of the computer's operating system, like GRUB, LILO or NTLDR. Modern personal computers have the ability of using their network interface card (NIC) for bootstrapping; on IA-32 (x86) and IA-64 (Itanium) this method is implemented by PXE and Etherboot.

2009-06-23T04:24:00.001-07:00

2. Difference between interrupt and trap

Interrupt
An interrupt is a hardware-generated event, usually caused by an I/O device requesting service. The interrupt signal causes a change of °ow within the system: an interrupt service routine (ISR) saves the CPU state, services the interrupt, then restores control to the interrupted process.

Trap
A trap, on the other and, is a software-generated interrupt. Traps are caused by 1) system calls and 2) exceptional software conditions (e.g. divide by 0). Other than the source and function, processing of traps and interrupts is the same.

Uses

Interrupt

Typical uses of interrupts include the following: system timers, disks I/O, power-off signals, and traps. Other interrupts exist to transfer data bytes using UARTs or Ethernet; sense key-presses; control motors; or anything else the equipment must do. A classic system timer interrupt interrupts periodically from a counter or the power-line. The interrupt handler counts the interrupts to keep time. The timer interrupt may also be used by the OS's task scheduler to reschedule the priorities of running processes. Counters are popular, but some older computers used the power line frequency instead, because power companies in most Western countries control the power-line frequency with a very accurate atomic clock. A disk interrupt signals the completion of a data transfer from or to the disk peripheral. A process waiting to read or write a file starts up again. A power-off interrupt predicts or requests a loss of power. It allows the computer equipment to perform an orderly shutdown. Interrupts are also used in typeahead features for buffering events like keystrokes.

Trap

The main purpose of a trap is to provide a fixed subroutine that various programs can
call without having to actually know the run-time address. MS-DOS is the perfect example.
The int 21h instruction is an example of a trap invocation. Your programs do not have
to know the actual memory address of DOS’ entry point to call DOS. Instead, DOS patches
the interrupt 21h vector when it loads into memory. When you execute int 21h , the 80x86 automatically transfers control to DOS’ entry point, whereever in memory that happens to
be.

2009-06-23T04:19:00.000-07:00

3. Monitor Mode

Monitor mode, or RFMON (Radio Frequency Monitor) mode, allows a computer with a wireless network interface card (NIC) to monitor all traffic received from the wireless network. Unlike promiscuous mode, which is also used for packet sniffing, monitor mode allows packets to be captured without having to associate with an access point or ad-hoc network first. Monitor mode only applies to wireless networks, while promiscuous mode can be used on both wired and wireless networks. Monitor mode is one of the six modes that 802.11 wireless cards can operate in: Master (acting as an access point), Managed (client, also known as station), Ad-hoc, Mesh, Repeater, and Monitor mode.

2009-06-23T04:02:00.000-07:00

4. User Mode

In User mode, the executing code has no ability to directly access hardware or reference memory. Code running in user mode must delegate to system APIs to access hardware or memory. Due to the protection afforded by this sort of isolation, crashes in user mode are always recoverable. Most of the code running on your computer will execute in user mode.

2009-06-23T03:57:00.000-07:00

6. Direct Memory Access

Direct memory access (DMA) is a feature of modern computers and microprocessors that allows certain hardware subsystems within the computer to access system memory for reading and/or writing independently of the central processing unit. Many hardware systems use DMA including disk drive controllers, graphics cards, network cards and sound cards. DMA is also used for intra-chip data transfer in multi-core processors, especially in multiprocessor system-on-chips, where its processing element is equipped with a local memory (often called scratchpad memory) and DMA is used for transferring data between the local memory and the main memory. Computers that have DMA channels can transfer data to and from devices with much less CPU overhead than computers without a DMA channel. Similarly a processing element inside a multi-core processor can transfer data to and from its local memory without occupying its processor time and allowing computation and data transfer concurrency.
Without DMA, using programmed input/output (PIO) mode for communication with peripheral devices, or load/store instructions in the case of multicore chips, the CPU is typically fully occupied for the entire duration of the read or write operation, and is thus unavailable to perform other work. With DMA, the CPU would initiate the transfer, do other operations while the transfer is in progress, and receive an interrupt from the DMA controller once the operation has been done. This is especially useful in real-time computing applications where not stalling behind concurrent operations is critical. Another and related application area is various forms of stream processing where it is essential to have data processing and transfer in parallel, in order to achieve sufficient throughput.

2009-06-23T03:44:00.000-07:00

DRAM

RAM

7. Difference of RAM and DRAM

These terms all refer to different types of computer memory, or RAM - Random Access Memory. The "random" part means that any area of the memory can be communicated with. When people talk about how much memory or RAM their computer has, they are usually referring to DRAM (or in newer systems, SDRAM). (S)DRAM is a computer's main memory that holds onto information for the mictorprocessor. The "D" stands for dynamic, meaning the RAM needs to have the information it's holding continuously renewed or "refreshed". SDRAM (Synchronous DRAM) is a newer faster type of DRAM. Designed to keep up with today's high-speed microprocessors, SDRAM can typically run at the same speed as the overall system.

2009-06-23T03:36:00.000-07:00

8. main memory
Refers to physical memory that is internal to the computer. The word main is used to distinguish it from external mass storage devices such as disk drives. Another term for main memory is RAM.

operating system

2009-06-18T04:05:00.000-07:00

7. Differentiate the design issues of OS between a stand alone PC and a workstation connected to a network

stand-alone PC
A desktop or laptop computer that is used on its own without requiring a connection to a local area network (LAN) or wide area network (WAN). Although it may be connected to a network, it is still a stand-alone PC as long as the network connection is not mandatory for its general use.

workstation
A significant segment of the desktop market are computers expected to perform as workstations, but using PC operating systems and components. PC component manufacturers will often segment their product line, and market premium components which are functionally similar to the cheaper "consumer" models but feature a higher level of robustness and/or performance. Notable examples of this are the AMD Opteron, Intel Xeon processors, and the ATI FireGL and Nvidia Quadro graphics processors.
A workstation class PC may have some of the following features:

support for ECC memory
a larger number of memory sockets which use registered (buffered) modules
multiple processors
multiple displays
run a "business" or "professional" operating system version

2009-06-18T03:49:00.001-07:00

1. The difference of OS in terms of user’s view and system’s view

User view

The user view of the computer varies by the interface being used. Most computer users sit in front of a PC, consisting of a monitor, keyboard, mouse and system unit. Such a system is designed for one user to monopolize its resources, to maximize the work that the user is performing. In this case,the operating system is designed mostly for ease of use, with some attention paid to performance, and none paid to resource utilization.

System View

We can view an operating system as a resource allocator. A computer system has many resources - hardware and software - that may be required to solve a problem. The operating system acts as the manager of these resources.
An operating system can also be viewed as a control program that manages the execution of user programs to prevent errors and improper use of the computer. It is especially concerned with the operation and control of I/O devices.

2009-06-18T03:49:00.000-07:00

2. Goals of OS

It is easier to define an operating system by what it does than what it is, but even this can be tricky. The primary goal of some operating system is convenience for the user. The primary goal of other operating system is efficient operation of the computer system. Operating systems and computer architecture have influenced each other a great deal. To facilitate the use of the hardware, researchers developed operating systems. Users of the operating systems then proposed changes in hardware design to simplify them. In this short historical review, notice how identification of operating-system problems led to the introduction of new hardware features.

2009-06-18T03:29:00.000-07:00

3. What’s the difference between batch system, multi programmed system, and time sharing systems?

batch system

A computer system that uses batch processing.

multi programmed system

A group of jobs that are ready to be executed is called job pool. Since there is more than one job that can be executed, it is possible for the operating system to make a decision about which job to execute next. That decision keeps CPU utilization as high as possible.In general, it is not possible for a single user to keep CPU or I/O devices busy at all times. Multiprogramming allows the system .to increase CPU utilization by ensuring that the CPU always has a job to execute.

time sharing systems

A technique permitting many users simultaneous access to a central computer through remote terminals.

2009-06-18T03:02:00.001-07:00

4. Advantage of parallel systems.
In terms of disproportional, Parallel systems usually give results which fall somewhere between pure plurality/majority and pure PR systems. One advantage is that, when there are enough PR seats, small minority parties which have been unsuccessful in the plurality/majority elections can still be rewarded for their votes by winning seats in the proportional allocation. In addition, a Parallel system should, in theory, fragment the party system less than a pure PR electoral system.

2009-06-18T02:59:00.000-07:00

5. Differentiate symmetric multi-processing and asymmetric multiprocessing.

Asymmetric multiprocessing (ASMP)

In asymmetric multiprocessing (ASMP), the operating system typically sets aside one or more processors for its exclusive use. The remainder of the processors run customer programs. As a result, the single processor running the operating system can fall behind the processors running customer programs. This forces the programs to wait while the operating system catches up, which reduces the overall throughput of the computer. In the ASMP model, if the processor that fails is an operating system processor, the whole computer can go down.

Symmetric multiprocessing (SMP)

Symmetric multiprocessing (SMP) technology is used to get higher levels of performance. In symmetric multiprocessing (SMP), any processor can run any type of thread. The processors communicate with each other through shared memory.
SMP computers provide better load-balancing and fault tolerance. Because the operating system threads can run on any processor, the chance of hitting a CPU bottleneck is greatly reduced. All processors are allowed to run a mixture of program and operating system code. A processor failure in the SMP model will only reduce the computing capacity of the computer.
SMP computers are inherently more complex than ASMP computers. A tremendous amount of coordination must take place within the operating system to keep everything synchronized. For this reason, SMP computers are usually designed and written from the ground up.

2009-06-18T02:55:00.000-07:00

6. Differentiate client server system and peer-to-peer system.

In a client-server network, there is one distinguished host which acts as the server, and all the clients connect to the server (not directly to each other). Therefore, if you were to draw a diagram of the network it would look like a star, with the server in the middle and connections radiating out to each client. In a peer-to-peer network, all hosts are of equal status, and may make connections arbitrarily to one another, so the graph of the network topology would have connections going every which way. The "master server" system is really just for when you have so much data that one machine can't act as the server - then you replace the "server" by its own client-server network with one "master server" and several "slave servers", all of which appear to the outside world (the original clients) as effectively a single entity.

2009-06-18T02:39:00.000-07:00

8. Define the essential properties of the following types of OS:

a. Batch
Batch os is os which analyzes your i/p and groups them into batchs .That is data in each batch is of similar characteristics.And then it performs operation on each individual batch.

b. Time sharing
TSOS stands for Time Sharing Operating System; it was an operating system for RCA (Radio Corporation of America) mainframes of the RCA Spectra 70 series.RCA was in the computer business until 1971. Then it was sold to Sperry Corporation; Sperry offered TSOS renaming it to VS/9. In the mid seventies, an enhanced version of TSOS was offered by the German company Siemens and was called BS2000 here. While Sperry (respectively Univac after the company was renamed) discontinued VS/9 in the early 80's, BS2000, now called BS2000/OSD is still offered by Fujitsu Siemens Computers and used on their mainframe customers primarily in Europe. TSOS was the first operating system that supported virtual addressing of the main storage. Beyond that it provided a unique user interface for both, time sharing and batch which was a big advantage over IBM's OS/360 or their successors MVS, OS/390 and z/OS as it simplified the operation.

c. real time
Real-time operating systems: They are used to control machinery, scientific instruments and industrial systems. An RTOS typically has very little user-interface capability, and no end-user utilities, since the system will be a sealed box when delivered for use. A very important part of an RTOS is managing the resources of the computer so that a particular operation executes in precisely the same amount of time every time it occurs. In a complex machine, having a part move more quickly just because system resources are available may be just as catastrophic as having it not move at all because the system is busy.

d. network
Network operating systems (NOS) typically are used to run computers that act as servers. They provide the capabilities required for network operation. Network operating systems are also designed for client computers and provide functions so the distinction between network operating systems and stand alone operating systems is not always obvious.

e. distributed
Distributed Operating Systems supports a transparent view of the entire network, in which users normally do not distinguish local resources from remote resources.

f. Handheld
A handheld PC's operating system determines not only what you see onscreen, but also how you interact with the device and what kind of services you can get from it. The two dominant handheld OSes are Palm and Pocket PC but Symbian and Linux are both up and coming. To help you decide which OS you want on your next handheld, here's a breakdown of these four operating systems plus a few of our hardware picks to get you started.

2009-02-25T01:47:00.000-08:00

1. What is the reason for technicians to wear special wrist grounding straps?

As a PC technician, you need to know how to set up a work environment so that the
risk of ESD damage is minimized as much as possible. This includes wearing certain
clothing/fabrics, using antistatic equipment and mats, and controlling environmental
conditions, such as humidity in the room. A wrist grounding strap is used to prevent electrostatic discharge when handling computer components. In more detail, it is a wire leading from a technician’s bodies (a wrist band with metal contact to the skin) to earth ground, with a high (1 megohm) resistance in it. This slowly discharges any static electricity that is built up on the body, to avoid discharging it into an electronic component. An electrostatic discharge (ESD) mat with similar connection to ground is also used to keep the electronic components at earth ground potential.

http://media.wiley.com/product_data/excerpt/53/04701339/0470133953.pdf

http://wiki.answers.com/Q/What_is_a_wrist_grounding_strap

2. After installing a new computer component why is it important to obtain the most current driver for it?
A device driver simplifies programming by acting as an abstraction layer between a hardware device and the applications or operating systems that use it. The higher-level application code can be written independently of whatever specific hardware device it will ultimately control, as it can interface with it in a standard way, regardless of the underlying hardware. Every version of a device, such as a printer, requires its own hardware-specific specialized commands. In contrast, most applications utilize devices (such as sending a file to a printer) by means of high-level device-generic commands such as PRINTLN (print a line). The device-driver accepts these generic high-level commands and breaks them into a series of low-level device-specific commands as required by the device being driven. Furthermore, drivers can provide a level of security as they can run in kernel-mode, thereby protecting the operating system from applications running in user-mode.

http://en.wikipedia.org/wiki/Device_Driver#Purpose

3. What are the steps required to install a peripheral device?

Installing a Peripheral
If you add a first or even second device to a basic system, you may have no conflicts, but as you add more, the chances are greater for a conflict. Each device uses one or more resources of the computer, and two devices cannot generally share the same one. If the CD-ROM, sound card, scanner, etc., that you add uses the same setting as an existing board, you have to figure out where the conflict is and choose another resource.
ISA, EISA AND Micro Channel Buses
The ISA bus was the original PC bus and does not have any advanced installation features. PCs that used the EISA and Micro Channel buses still had configuration problems, but had two advantages. First, when a board is added, a setup program was run to install the board, and conflicts were identified ahead of time. Although you still had to participate in this "plug and tell" capability, it was better than the "plug and hope" offered by ISA-bus cards.
Secondly, the boards were configurable by software, which eliminated the need to set switches or jumpers on the boards themselves. If you have to change a setting, you did not have to pull the board out of the socket in order to do it. You ran the setup program and selected the configuration option.
The Resources
The PC uses several resources to transfer signals to a peripheral device, and the settings associated with these resources are often arbitrary.
1. IRQ
2. I/O address (port address)
3. Memory address
Most peripherals use an IRQ and an I/O address. Many use a memory address. When you install a new board in your PC, you MUST read the installation manual in order to find out what the initial settings are and how to change them if necessary. If a new board uses the same setting as an existing board, it won't work properly or at all. Or, it will work and the old one won't, or both won't work.

http://www.answers.com/topic/how-to-install-a-pc-peripheral

4. If a newly installed peripheral device does not function properly what steps can be taken to correct the problem?

First, the device doesn't work properly; second, the user remove drivers; third, bug in the software and so on. If device is working properly, what you can do is turn everything off. Then start the pc, wait while it's booting up. After you logged on and windows started turn your device. If nothing was broken it will work again.

http://wiki.answers.com/Q/A_user_reports_that_a_peripheral_device_that_was_installed_correctly_last_week_has_not_been_functioning_since_the_PC_was_booted_today_All_other_PC_functions_are_working_properly_What_are_three_thing

5. Explain the technique used to help protect data on a hard drive when doing a clean install?

One of the techniques available to help protect data is to divide the hard drive into multiple partitions. With a clean install, many technicians prefer to create one partition for dupgraded widata files.

http://eskilstuna.se/upload/85680/Svar%20kapitel%202.pdf

6. Explain what a software patch is.

A patch is a piece of program code that can correct a problem or functionality of an application program or OS. They are usually provmanufacturer to repair a known vulnerability or reported problem.

http://eskilstuna.se/upload/85680/Svar%20kapitel%202.pdf

2009-01-28T02:49:00.000-08:00

DOS and Windows

MS-DOS FDISK Main Menu
Most DOS fdisk programs, including the fdisk program that came with the original Windows 95, are only capable of creating FAT partitions of types FAT12 and FAT16.
A derivative of the MS-DOS fdisk was provided with Windows 95, Windows 98, and later Windows Me. Only those fdisk versions shipping with Windows 95B or later are able to manipulate FAT32 partitions. Windows 2000 and later do not use fdisk, they have the Logical Disk Manager feature, as well as DiskPart.
Unlike the fdisk programs for other operating systems, the fdisk programs for DOS and Windows 9x/Me not only alter data in the partition table, but will also overwrite many sectors of data in the partition itself. Users must be sure the correct disk/partition has been chosen before using a DOS/Windows fdisk for partitioning.
The implementation of fdisk in FreeDOS has many advanced features and is free software.

2009-01-28T02:21:00.000-08:00

Windows XP screen shots

In Windows XP Microsoft has made the file browsing prettier using large icons and thumbnail views.

Once you have "activated" Windows with Microsoft (or installed a crack) you may continue to use Windows normally.
This is the default screen you will see when you first log in to Windows XP.

Linux screen shots

Ubuntu 7.04 - Mozilla Firefox 2.0.0.3

Ubuntu 7.04 - Login screen after installation and restart

Windows Vista screen shots

Windows Vista, Windows Explorer with properties of the device

Windows Vista, control panel with classic view

Windows Vista (Windows version 6.0) contains the new user interface Aero. The start menu has a round start button without text now. New characteristics are three-dimensional effects, the transparent representation and freely scalable symbols. To see all visual features a graphiccard with DirectX 9.0 support is required. The known interface of Windows XP can be activated alternatively. The PC should at least contain a processor with 2 ghz, 512 mbyte RAM and at least 10 GByte of free harddisk storage.

Windows 2000 screen shots

Windows 2000 - with Servicepack 3 other standard software for middleware can be more easily specified

Windows 2000 - boot screen (16 colors)

Microsoft released this new Windows version 5.0, Build 2195 in February 2000. It is the desktop operating system of the new Windows 2000 platform for x86 architecture and be completed by the versions Windows 2000 Server, Windows 2000 Advanced Server and Windows 2000 Datacenter Server.Windows 2000 unites defined roughly the user-friendliness, pug & play and USB device support of Windows 98 and the safety and stability of the Windows NT family. The update to this new operating system is possible from Windows 95, 98 and Windows NT 3.51, 4.0. It is a multitasking, multiprocessing operating system and supports up to 2 processors of the x86 32- bit and 64 bit architecture with SMP.

2009-01-22T22:15:00.000-08:00

2009-01-19T03:16:00.001-08:00

NOS certifications

5.2.2 Worksheet: NOS Certifications and Jobs
Network Operating System(s) covered:The Microsoft Certified Systems Engineer (MCSE) credential is the premier certification for professionals who analyze the business requirements and design and implement the infrastructure for business solutions based on the Microsoft Windows 2000 platform and Microsoft Windows Server System. Implementation responsibilities include installing, configuring, and troubleshooting network systems. Learn more about MCSE job functions by reading the MCSE Job Task Analysis (Microsoft Word 925 KB).Courses/Training required for Certification:Microsoft Certified Systems Engineer (MCSE) CertificationCourses/ Training required for Certification:The Windows 2000 track of the MCSE credential is designed for information technology (IT) professionals working in the typically complex computing environment of medium to large organizations.An MCSE candidate should have at least one year of experience implementing and administering a network operating system in environments with the following characteristics:200 to 26,000 supported usersFive to 150 physical locationsTypical network services and applications including file and print, database, messaging, proxy server or firewall, dial-in server, desktop management, and Web hostingConnectivity needs including connecting individual offices and users at remote locations to the corporate network and connecting corporate networks to the InternetImplementing and administering a desktop operating systemDesigning a network infrastructureFor more information on additional requirements to earn the MCSE credential, see the MCSE Certification Requirements

Network Operating System(s) covered:
CISCO

Certification(s) title: Cisco ASA Specialist

Cisco security certifications focus on the growing need for knowledgeable network professionals who can implement complete security solutions. The ASA Specialist certification identifies individuals who possess in-depth expertise with implementing security technologies using the Adaptive Security Appliance (ASA) technologies, especially firewall and VPN functionality. Other topics include ACL, AAA, advanced protocol handling, remote access VPN, secure socket layer VPN, site-to-site VPNs, failover, and security appliance management. Cisco ASA Specialists possess the ability to describe, configure, verify and manage the ASA products and the Adaptive Security Device Manager (ASDM).Courses/Training required for Certification:Cisco ASA Specialist Prerequisites: CCNA SecurityCisco ASA Specialist Exams and Recommended Training:
1. Required Exam(s)
a.)642-524 SNAF
b.)642-515 SNAA
2. Recommended Training:
a.)Securing Networks with ASA Foundation
b.)Securing Networks with ASA Advanced

Network Operating system(s) covered:

Red Hat Certified Engineer (RHCE) is a performance-based test that measures actual competency on live systems. Called the "crown jewel of Linux certifications," RHCE proves an individual's ability to configure networking services and security on servers running a Red Hat OS. RHCE was recently named the hottest certification in all of IT by CertCities.com.
Certification title:Red Hat Certified Engineer (RHCE)
Courses:Red Hat Training:Red Hat Certifications: Classroom TrainingRed Hat Training provides classroom-based courses at convenient worldwide locations and in a variety of topics. Browse through the complete list of courses below or select a track on the right-hand side of this page. Visit the Classroom Student Guide to find out more
Diagnostic Software1. Based on your research, list at least two different hard drive manufacturers.

Manufacturer: western digital

Data Lifeguard Tools 11.2 for Windows
File Name: Dlgsetup11_win.zip
File Size: 3.50 MB
Version: Version 11.2
Publish Date: April, 2006

Description
The downloadable Data Lifeguard Tools now comes in both DOS and Windows versions and was written specifically for the installation of Western Digital EIDE hard drives. If your computer system already has a hard drive installed with an operating system of Windows 98SE or greater, you should use the Windows version of Data Lifeguard for best results. The DOS version is required if installing a hard drive in a new system without existing operating system support. If you plan on copying the contents of a boot drive, Western Digital recommends using the DOS version of Data Lifeguard Tools.

Manufacturer: Maxtor

Software Name: SCSIMax
File Name: SCSIMax.exeFile
Size: 70.0 kb
Version: v1.21
Publish Date: 05.14.2003

Description:
SCSiMax is a diagnostic utility for all Maxtor/Quantum@ SCSI Hard Disk Drive supporting self-monitoring, analysis, and reporting technology (S.M.A.R.T.). This test will determine Hard Drive integrity in a short period of time, with a high degree of confidence.

2009-01-14T03:11:00.000-08:00

Installation of Windows XP

Step #1: Plan your installation

When you run the Windows XP Professional Setup program, you must provide information about how to install and configure the operating system. Thorough planning can make your installation of Windows XP Professional more efficient by helping you to avoid potential problems during installation. An understanding of the configuration options will also help to ensure that you have properly configured your system.

Here are some of the most important things you should take into consideration when planning for your XP installation:

Check System Requirements
Check Hardware and Software Compatibility
Determine Disk Partitioning Options
Choose the Appropriate File System: FAT, FAT32, NTFS
Decide on a Workgroup or Domain Installation
Complete a Pre-Installation Checklist

Step #2: Beginning the installation process

You can install Windows XP in several methods - all are valid and good, it all depends upon your needs and your limitations.

Manual installations usually come in 3 flavors:
Boot from CD - No existing partition is required.
Boot from the 6 Setup Boot Disks, then insert the CD - No existing partition is required
Boot from an MS-DOS startup floppy, go to the command prompt, create a 4GB FAT32 partition with FDISK, reboot, format the C partition you've created, then go to the CD drive, go into the I386 folder, and run the WINNT.EXE command.
Run an already installed OS, such as Windows NT 4.0 Server. From within NT 4.0 go to the I386 folder in the W2K installation CD and run the WINNT32.EXE command.
If you want to upgrade a desktop OS such as Windows 98 into Windows 2000 Professional you can follow the same procedure as above (You cannot upgrade Windows 98 into W2K Server).

Step #3: The text-based portion of the Setup program

The setup process begins loading a blue-looking text screen (not GUI). In that phase you will be asked to accept the EULA and choose a partition on which to install XP, and if that partition is new, you'll be asked to format it by using either FAT, FAT32 or NTFS.

Start the computer from the CD.
You can press F6 if you need to install additional SCSI adapters or other mass-storage devices. If you do you will be asked to supply a floppy disk with the drivers and you CANNOT browse it (or a CD for that matter). Make sure you have one handy.

If you want, you can press F2 to run the ASR sequence. For that you need a good backup created by the Windows XP backup program, and the ASR floppy disk. If you plan to install a new copy of XP - don't do anything.

Setup will load all the needed files and drivers.

Select To Setup Windows XP Professional Now. If you want, and if you have a previous installation of XP, you can try to fix it by pressing R. If not, just press ENTER.

Read and accept the licensing agreement and press F8 if you accept it.

Select or create the partition on which you will install Windows XP Professional. Depending upon your existing disk configuration choose one of the following:

If the hard disk is unpartitioned, you can create and size the partition on which you will install Windows XP Professional.
If the hard disk is already partitioned, but has enough unpartitioned disk space, you can create an additional partition in the unpartitioned space.
If the hard disk already has a partition that is large enough, you can install Windows XP Professional on that partition. If the partition has an existing operating system, you will overwrite that operating system if you accept the default installation path. However, files other than the operating system files, such as program files and data files, will not be overwritten.
If the hard disk has an existing partition, you can delete it to create more unpartitioned space for the new partition. Deleting an existing partition erases all data on that partition.

If you select a new partition during Setup, create and size only the partition on which you will install Windows XP Professional. After installation, use Disk Management to partition the remaining space on the hard disk.

8. Select a file system for the installation partition. After you create the partition on which you will install Windows XP Professional, you can use Setup to select the file system with which to format the partition. Windows XP Professional supports the NTFS file system in addition to the file allocation table (FAT) and FAT32 file systems. Windows Server 2003, Windows XP Professional, Windows 2000, and Windows NT are the only Microsoft operating systems that you can use to gain access to data on a local hard disk that is formatted with NTFS. If you plan to gain access to files that are on a local Windows XP Professional partition with the Microsoft Windows 95 or Windows 98 operating systems, you should format the partition with a FAT or FAT32 file system. We will use NTFS.

9. Setup will then begin copying necessary files from the installation point (CD, local I386 or network share).

10. Note: If you began the installation process from an MS-DOS floppy, make sure you have and run SMARTDRV from the floppy, otherwise the copying process will probably last more than an hour, perhaps even more. With SMARTDRV (or if setup was run by booting from CD) the copying will probably last a few minutes, no more than 5 max.

11. The computer will restart in graphical mode, and the installation will continue.

Step #4: The GUI-based portion of the Setup program

The setup process reboots and loads a GUI mode phase.

It will then begin to load device drivers based upon what it finds on your computer. You don't need to do anything at this stage.

1. Click Customize to change regional settings, if necessary.

Current System Locale - Affects how programs display dates, times, currency, and numbers. Choose the locale that matches your location, for example, French (Canada).
Current Keyboard Layout - Accommodates the special characters and symbols used in different languages. Your keyboard layout determines which characters appear when you press keys on the keyboard.

If you don't need to make any changes just press Next.
If you do need to make changes press Customize and add your System Locale etc.

2. Type your name and organization.

3. Type the product key.

4. Type the computer name and a password for the local Administrator account. The local Administrator account resides in the SAM of the computer, not in Active Directory. If you will be installing in a domain, you need either a pre-assigned computer name for which a domain account has been created, or the right to create a computer account within the domain.

5. Select the date, time, and time zone settings.

6. Setup will now install the networking components.

After a few seconds you will receive the Networking Settings window. BTW, if you have a NIC that is not in the HCL and XP cannot detect it, or if you don't have a NIC at all, setup will skip this step and you will immediately go to the final phase of the setup process.

Press Next to accept the Typical settings option if you have one of the following situations:

You have a functional DHCP on your network.
You have a computer running Internet Connection Sharing (ICS).
You're in a workgroup environment and do not plan to have any other servers or Active Directory at all, and all other workgroup members are configured in the same manner.

Otherwise select Custom Settings and press Next to customize your network settings.

7. One thing you CAN do is to uninstall the Qos Packet Scheduler. Click it and press the Uninstall button. If you want to keep it you can simply remove the mark from the QoS check-box. In anyway you can later install or uninstall it if you want.
Keep the TCP/IP, Client for Microsoft Networks and the File and Print Sharing options selected.

8. Highlight the TCP/IP selection and press Properties.
In the General tab enter the required information. You must specify the IP address of the computer, and if you don't know what the Subnet Mask entry should be - you can simply place your mouse pointer over the empty area in the Subnet Mask box and click it. The OS will automatically select the value it thinks is good for the IP address you provided.
If you don't know what these values mean, or if you don't know what to write in them, press cancel and select the Typical Settings option. You can easily change these values later.

9. In the Workgroup or Domain window enter the name of your workgroup or domain.

A workgroup is a small group of computers on a network that enables users to work together and does not support centralized administration.
A domain is a logical grouping of computers on a network that has a central security database for storing security information. Centralized security and administration are important for computers in a domain because they enable an administrator to easily manage computers that are geographically distant from each other. A domain is administered as a unit with common rules and procedures. Each domain has a unique name, and each computer within a domain has a unique name.

If you're a stand-alone computer, or if you don't know what to enter, or if you don't have the sufficient rights to join a domain - leave the default entry selected and press Next.

If you want to join a domain (NT 4.0 domain of W2K/2003 Active Directory domain) enter the domain's name in the "Yes, make this computer a member of the following domain" box.

To successfully join a domain you need the following:

The person performing the installation must have a user account in Active Directory. This account does not need to be the domain Administrator account.

and

The computer must have an existing computer account in the Active Directory database of the domain that the computer is joining, and the computer must be named exactly as its domain account is named.

The person performing the installation must have appropriate permission to create a domain account for the computer during installation.
Also, you need to have connectivity to the domain's domain controllers (only to the PDC if on an NT 4.0 domain) and a fully functional DNS server (only in AD domains).

Enter the Active Directory domain name (in the form of xxx.yyy, for example: DPETRI.NET) or the NetBIOS name of the NT 4.0 domain (in the form of xxx, for example: DPETRI). Press Next.

Note: If you provide a wrong domain name or do not have the correct connectivity to the domain's DNS server you will get an error message.

A username/password window will appear. Enter the name and password of the domain's administrator (or your own if you're the administrator on the target domain).
Note: Providing a wrong username or password will cause this phase to fail.

10. Next the setup process will finish copying files and configuring the setup. You do not need to do anything.

11. After the copying and configuring phase is finished, if XP finds that you have a badly configured screen resolution it will advise you to change it and ask you if you see the new settings right.
BTW, the minimum supported screen resolution in XP is 800X600.
12. Setup finishes and boots Windows XP.

13. A Welcome screen is the first thing you see. The computer checks your Internet connectivity (required for the mandatory Activation and voluntary Registration processes).

You will be asked to register your copy of XP. You can decline if you want.

14. XP will ask you for the default username that will log onto this computer. You can enter as many as 5 users, but you can create more after the installation is finished.

BTW, the Administrator is not shown as a valid logon option

15. That's it! you're done!

2009-01-14T03:03:00.000-08:00

Latest Software

Microsoft

Windows 7 (formerly codenamed Blackcomb and Vienna) is the next release of Microsoft Windows, an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops, Tablet PCs, and media center PCs. Microsoft stated in 2007 that it is planning Windows 7 development for a three-year time frame starting after the release of its predecessor, Windows Vista, but that the final release date will be determined by product quality. Unlike its predecessor, Windows 7 is intended to be an incremental upgrade with the goal of being fully compatible with existing device drivers, applications, and hardware.Presentations given by the company in 2008 have focused on multi-touch support, a redesigned Windows Shell with a new taskbar, a home networking system called HomeGroup, and performance improvements. Some applications that have been included with prior releases of Microsoft Windows, most notably Windows Mail, Windows Calendar, Windows Movie Maker, and Windows Photo Gallery, are no longer included with the operating system; they are instead offered separately (free of charge) as part of the Windows Live Essentials suite.

Development

Originally, a version of Windows codenamed Blackcomb was planned as the successor to Windows XP and Windows Server 2003. Major features were planned for Blackcomb, including an emphasis on searching and querying data and an advanced storage system named WinFS to enable such scenarios. Later, Blackcomb was delayed and an interim, minor release, codenamed "Longhorn" was announced for 2003. By the middle of 2003, however, Longhorn had acquired some of the features originally intended for Blackcomb. After three major viruses exploited flaws in Windows operating systems within a short time period in 2003, Microsoft changed its development priorities, putting some of Longhorn's major development work on hold in order to develop new service packs for Windows XP and Windows Server 2003. Development of Longhorn was also "reset" in September 2004.
Blackcomb was renamed Vienna in early 2006, and again to Windows 7 in 2007. In 2008, it was announced that Windows 7 would also be the official name of the operating system.

Features

Windows 7 includes a number of new features, such as advances in touch, speech, and handwriting recognition, support for virtual hard disks, improved performance on multi-core processors, improved boot performance, and kernel improvements.
Windows 7 adds support for systems using multiple heterogeneous graphics cards from different vendors, a new version of Windows Media Center,[25] Gadgets being integrated into Windows Explorer, a Gadget for Windows Media Center, the ability to visually pin and unpin items from the Start Menu and Taskbar, improved media features, the XPS Essentials Pack being integrated, Windows PowerShell Integrated Scripting Environment (ISE), and a redesigned Calculator with multiline capabilities including Programmer and Statistics modes along with unit conversion.
Many new items have been added to the Control Panel including: ClearType Text Tuner, Display Color Calibration Wizard, Gadgets, Recovery, Troubleshooting, Workspaces Center, Location and Other Sensors, Credential Manager, Biometric Devices, System Icons, Action Center, and Display. Windows Security Center has been renamed the Windows Action Center (Windows Health Center and Windows Solution Center in earlier builds) which encompasses both security and maintenance of the computer.
The taskbar has seen the biggest visual changes, where the Quick Launch toolbar has been merged with the task buttons to create an enhanced taskbar or what Microsoft internally refers to as the "Superbar". This enhanced taskbar also enables the Jump Lists feature to allow easy access to common tasks. The revamped taskbar also allows the reordering of taskbar buttons.
Screenshots have appeared demonstrating a new feature called 'Peek'. Peek is a quick way of making all visible windows transparent for a quick look at the desktop. A Microsoft spokesman said that "this will be useful for users who want a quick look at the news" in reference to RSS gadgets on the desktop.[citation needed]
For developers, Windows 7 includes a new networking API with support for building SOAP based web services in native code (as opposed to .NET based WCF web services), new features to shorten application install times, reduced UAC prompts, simplified development of installation packages, and improved globalization support through a new Extended Linguistic Services API.
At WinHEC 2008 Microsoft announced that color depths of 30-bit and 48-bit would be supported in Windows 7 along with the wide color gamut scRGB (which for HDMI 1.3 can be converted and output as xvYCC). The video modes supported in Windows 7 are 16-bit sRGB, 24-bit sRGB, 30-bit sRGB, 30-bit with extended color gamut sRGB, and 48-bit scRGB.

Sun Microsystems Delivers Solaris 10 10/08 Release

Latest Enhancements to Award Winning Solaris 10 Operating System
SANTA CLARA, CALIF. October 31, 2008 Sun Microsystems, Inc. (NASDAQ: JAVA) today announced the latest version of the Solaris 10 Operating System (OS) - Solaris 10 10/08. The new version builds on the core strengths of the Solaris 10 OS to help customers maximize asset usage and systems performance, manage datacenter complexity, preserve business continuity and reduce costs. Solaris 10 10/08 includes numerous product updates and enhancements, several of which were done through the OpenSolaris community.

New Features in Solaris 10 10/08

ZFS File System Enhancements: The ZFS file system has been enhanced with recent work from the OpenSolaris community, providing ease of data management with no additional cost for acquisition or support. The new version of Solaris ZFS file system offers increased data integrity and expanded dataset recovery capabilities. ZFS file system can be used as the sole file system for any class of system, with support for booting and/or for use as a root file system.
Virtualization and Solaris Containers Updates: Solaris 10's virtualization technologies, such as Solaris Containers, have been enhanced with new features to make it even easier for customers to migrate workloads among Solaris systems and reducing the administrative overhead necessary to move a container between unlike system configurations.
Intel architecture optimization: Sun and Intel continue to collaborate to help ensure Solaris 10 will support for Intel's latest Intel Xeon processor line so customers can benefit from the improved functionality, power efficiency and reliability of systems that contain those CPUs. In addition Sun and Intel have achieved several new world records(*) for Solaris 10 on Sun Systems powered by Intel Xeon processor 7400 series.
Compatibility continues to be a key feature of the Solaris 10 OS. Through the Solaris OS update model, customers can easily upgrade to Solaris 10 10/08 without requiring additional hardware/software upgrades or recertification of existing projects and applications. In addition, Solaris 10 10/08 preserves full compatibility with over 7,000 third-party products and customers internally-developed applications.
With built-in, open source, no-cost virtualization via Solaris Containers and Sun Logical Domains (LDoms), Sun and Fujitsu's recently announced Sun SPARC Enterprise T5440 server is an ideal platform for consolidating hundreds of existing enterprise class workloads onto a single system. Additionally, for existing Solaris OS customers, the Solaris 8 and 9 Containers capability enables customers to run multiple Solaris 8 or 9 environments on a single SPARC-based system. As a result, customers can quickly and easily move existing physical environments to virtual containers on Solaris 10 and take advantage of the performance, scale and cost savings of new SPARC Enterprise CMT-based servers today.

Mandriva Linux

Mandriva Linux (formerly Mandrakelinux or Mandrake Linux) is an operating system created by Mandriva (formerly Mandrakesoft). It uses the RPM Package Manager. The product lifetime of Mandriva Linux releases is 18 months for base updates and 12 months for desktop updates.

Like its predecessors, Mandriva is a KDE-centric distribution. GNOME is available, but it is slightly less customized, with its default icons unchanged. By default, both KDE and GNOME feature a simplified but incomplete menu, including black and white wallpaper that looks like a visionary penguin gazing heroically upwards. If you ignore warnings and log in to a desktop as root, the default wallpaper is bright red, to remind you of the potential damage that a root user can inflict.
In most software categories, Mandriva's menus offer a limited but representative sample of what's available. For Web browsers, for instance, it offers Epiphany, Firefox, Konqueror, and Opera. Similarly, Mandriva offers three choices for system administration: the KDE Control Center, the Mandrake Control Center, and Webmin for advanced users and networking. While experienced users may miss their favorite software, Mandriva's policy generally balances introducing newcomers to the available variety without overwhelming them. Some software, including the GIMP, is installed, but not on the default menus.
As might be expected with a commercial distribution, the standard software is current to a month before the software's release in mid-October 2005. The free software includes a 2.6.12 kernel, Firefox 1.06, and GIMP 2.2, the non-free software Acrobat Reader 7.0, Flash 7.0, Opera 8.5, and Skype 1.2.0.17. The most unusual feature in the general selection of software is OpenOffice.org 1.1.5, as opposed to a release candidate of 2.0. Mandriva also opted for GCC 4.0 rather than Java, and apparently built OpenOffice.org with it.
New to Mandriva 2006 is Kat, a Mandriva-sponsored desktop search tool similar to Google's Desktop Search. Cataloging both file metadata and contents, Kat currently supports a wide variety of graphics formats and a more limited selection of text formats, including PDF, HTML, Microsoft Word, Excel, OpenOffice.org 1.0, and OpenDocument. It requires an OS with lnotify activated; lnotify is a kernel module originally designed to search logs for suspect entries and the running of the kat daemon. Once set up, it provides quick and detailed responses. However, considering that Mandriva attempts to organize users by adding subdirectories such as Documents, Download, and Pictures to each home directory, I am uncertain about what advantages Kat itself offers over well-organized directories and a file manager in everyday computing.
The most noticeable feature of the Mandriva desktop are the more than 20 wizards. They vary from the multi-paged guide to setting up Evolution to Mandrake-specific ones such as the message box for setting OpenOffice.org to use either Microsoft Office or its native format.
On the whole, these wizards have the same strengths and weaknesses as similar helper applications on Windows. On one hand, they help new users to ramp up quickly. On the other hand, they rarely tell users how to change settings on their own. Granted, many users may not care to edit configuration files, but they could at least be told how to change the settings within the graphical program itself.
As far as I can tell, the software selection shows few if any legacies from Lycoris. Unique features of Lycoris, such as AI2 (Advanced Application Integration Infrastructure), a third-party installer, or the remote access assistance, a tool to enable remote login for technical support, have yet to find their way into Mandriva. Nor does Mandriva offer any of Lycoris' proprietary font packs. Conectiva's contributions to the default desktop seem equally sparse, except for a possible merging of its control center with Mandrake's.

2009-01-14T01:55:00.000-08:00

Hardware

Latest processor

Desktop

Extreme Gaming with the Intel® Core™ i7 Processor Extreme Edition

The ultimate immersive gaming experience Conquer the world of extreme gaming with the highest performing desktop processor on the planet: the Intel® Core™ i7 processor Extreme Edition.‡1 With intelligent multi-core technology that kicks into overdrive as your activity becomes more intense, it delivers breakthrough performance in gaming. Plus, multitask demanding applications up to 25% faster‡2 and unleash amazing power for digital media.

Features

Adrenaline on a chip

More threads = more speed

Fast and efficient multitasking

Server

Intel® Xeon® processor 7400 series

Extending today's lead in virtualization performance with built-in hardware assisted features and breakthrough gains in performance and energy efficiency²
Built for data-demanding enterprise applications with up to 6 cores and a large shared 16MB L3 cache per processor, enabling more transactions per server
More headroom, improved reliability, and the highest scalability available for large scale server consolidation and business-critical virtualization

Notebooks/Laptops

Intel® Centrino® 2 with vPro™ Technology

Keep your workforce more secure, managed, and mobile. With security and manageability built right onto the chip, Intel® Centrino® 2 with vPro™ technology provides hardware-assisted remote isolation, diagnostics, and repair, so you can manage your mobile workforce remotely, even if the system's OS is unresponsive.¹ And with exceptional dual-core performance, 5X better wireless performanceΩ and the longest possible battery life.²
Now you can also get notebooks with Intel Centrino 2 with vPro technology in astonishingly thin and light packages. As the smallest version of Intel® Centrino® processor technology yet-50 percent smaller-you're most mobile workforce can enjoy the sleekest full-featured and performance packed notebooks³ along with improved energy efficiency and power savings.°

Features and benefits

Best for business

Mobile performance
Increased energy-efficiency
Longer battery life
Faster, more predictable wireless

Expansion Slot

ASUS Launches the Latest Z7S WS with Superb Expansion Options

Taipei, Taiwan, February 26, 2008 -Catering to users who need a powerful motherboard with high speeds and great expansion slot interface support, ASUS, worldwide leader in motherboard design and production, has today released the Z7S WS workstation motherboard. This innovative motherboard is equipped with dual socket 771 and utilizes the latest Intel® 5400 chipset for vigorous performance. It also supports fully buffered DDR2 800MHz dual-channel memory, dual PCI Express 2.0 x16 lanes; and comes in the compact CEB form factor. With this innovative motherboard, users will enjoy convenient slot expansion and enjoy fast and efficient work efficiency.High Efficiency with Multiple High Speed Expansion SlotsThe multiple slot interfaces increase expansion choices and allows users to obtain high data transmission speeds. Supporting dual PCIe 2.0 x 16 for double the normal bus bandwidth from 2.5 Gb/s to 5.0 Gb/s, users will truly be able to accomplish more tasks in a much shorter time; while enjoying backward compatibility with previous PCIe 1.1 standards. The Z7S WS also showcases PCI-X slots for more convenience on slot expansion, and is able to bring about full speeds for Gigabit Ethernet, SCSI RAID and other PCI-X devices.Compact Board Size with Dual CPU Support and Rich I/OThe Z7S WS is well equipped with dual CPU sockets, 6 FB-DIMMs, and rich I/O; and still fits into the compact CEB form factor (12" x 10.5") - allowing users and enthusiasts to build up a small and compact whilst extremely powerful dual CPU workstation system with great performance.Heat-pipe Solution for Noiseless EnvironmentsEquipped with ASUS' innovative heat-pipe solution, the Z7S dissipates heat efficiently. The Z7S's particular heat-pipe design is made to increase durability, life spans and enhance thermal capacity. It also provides highly efficient operations with less heat than traditional heat sink designs.Discrete Audio MIO Card for Improved SoundThe MIO audio card offers great sound quality to complement the robust video power. This card offers enhanced signal-to-noise ratio in a 7.1 surround channel setup - delivering exhilarating surround sound for professional and entertainment usage.Exclusive MemCoolTM Support for Enhanced Thermal SolutionsThe optional ASUS Patented MemCool Kit maximizes Fully-buffered DIMM performance by eliminating the potential risk of system memory throttling from over-temperature; as well as minimizing the system integration effort of SI for thermal & acoustic solutions.Easy and Convenient InstallationsUsers will also enjoy the specially designed "extra" features that come with the Z7S WS. With Q-Connector, users can connect and disconnect chassis front panel cables in one easy step with just one complete module. This unique adapter eliminates the trouble of plugging in one cable at a time - making connections quick and accurate. Secondly, ASUS' Q-Shield does without the usual "fingers" of traditional gaskets - making it convenient, easy and safe to install without the scratches and cuts like before. The Q-Shield also has better electric conductivity to ideally protect the motherboard against static electricity and shield users against harmful Electronic Magnetic Interference (EMI).

2008-11-05T21:38:00.001-08:00

mouse with speakermonitor

central processing unit

motherboard

system unit

My Personal Computer