Operating System Options and Installation Methods

An OS is installed on the computers' hard disk, inside an area called hard disk partition. There are several ways for installing a new operating system. The installation method is based on the system hardware and end-user requirements. Generally, you have four basic options for the installation of a new operating system:

Clean Installation

We can perform a clean installation on a new computer or in those cases where there is no upgrade path between the current operating system and the new one. This type of installation deletes all data on the hard disks partition where the current operating system is installed. A new PC requires, of course a clean installation. You can also do a clean install when the current operating system installation has corrupted files or does not work properly.

Upgrade Installation

Sometimes, it is also possible to perform an upgrade. When you perform an upgrade, OS configuration settings, installed programs and data are preserved. With this installation you have nothing to worry about, because you will not lose any personal data. You will just replace the old operating system files with the new, upgraded files. However, keep in mind that after the upgrade the applications and drivers that are incompatible with the new OS will not work as expected.

Multi-boot Installation

Another option is to install multiple operating systems on a single computer. You can install each OS inside a different disk partition and this way every OS will have its own files and configuration settings. On multi-boot installations, the users see a menu when they open their computers and they have to select the desired OS. Of course, only one operating system can run at a time.

Virtualization

This is relative new technique that is often used on servers. With virtualization we can run numerous copies of an operating system on a single set of hardware and create this way several virtual machines. Every single virtual machine works like a separate computer. This technology makes a single physical hardware resource to appear like multiple logical resources.

Before starting any operating system installation you have to make sure that all the hardware is certified to work with the new operating system. Also confirm that the hardware resources meet the minimum installation requirements. Moreover, when you perform an upgrade it is a very good practice to perform a virus scan before starting the installation and a complete full backup of all your personal data.

One method that helps you protect your data is this: Create multiple partitions on the hard disk and install a different OS on each partition. Then copy all your data inside an empty partition that does not contain an OS. This way you can upgrade the operating system without the risk of losing any data. Backup and recovery of data files is also easier with this design.

It is also important to decide the type of file system to use. The file system controls how the OS stores and tracks the files. There are several different file systems available. The most well-known are: FAT 32, NTFS, HPFS, ext2 and ext3. Every operating system is designed to use one or more of these file systems. There are advantages and disadvantages on every file system. Careful consideration should be made to the type of file systems supported by the selected OS and the benefits of each.

You can find several programs to modify the partitioning structure and file system of a hard drive after installation, but it is better to avoid them if possible. When modifying either the file system or partition structure on a hard drive, data loss may result. Careful planning can help preserve the integrity of the data.

Operating System Market Share

The quantitative future estimates from analysts, which we use as the basis for our discussions, must of course�as with any predictions�be taken carefully. Our main goal is to use them to extract and illustrate significant market trends. To start with, consider Figure 3.6, from Gartner Group data from November 2003 and showing server market trends sorted by the operating system provided with the servers.

The strong increase in sales for Linux and Windows is obvious. It is likely that Windows�s growth will be mostly in the midrange, as the high end is the hunting ground for proprietary systems and UNIX. Netware is expected to undergo a noticeable reduction in market.

Linux�s market share is expected to grow noticeably. This OS seems to have a promising future in the domain of dedicated servers (that is, servers which support a single application).

Among the proprietary versions of UNIX, we see that AIX�s share is expected to grow while those of HP-UX and of Solaris are expected to stay stable at best. For HP-UX, the seamless transition offered to customers between HP�s PA architecture and IA-64 is a factor in reducing the erosion of HP-UX�s market share. Since HP has not announced any intention to give access to HP-UX outside OEM agreements, its market share will be strictly limited to systems developed by HP.

For Solaris, we should note that Sun has an IA-32 port. The battle between the different UNIX vendors will be interesting to watch, not least because it looks as though the players will be fighting over a shrinking field as they lose share to Linux and Windows Server 2003.

This shrink in market share is an effect of the competition that Windows and Linux are offering to UNIX systems in the low-end and midrange. The introduction of systems based on IA-64 (Itanium) is likely to relaunch the sales of UNIX on Intel platforms, in particular in midrange and high-end systems. And we should note that the various UNIX variants have had time and experience enough to reach a level of maturity and reliability that allows them to attack enterprise-critical systems, previously the domain of proprietary mainframe systems.

Windows looks set to dominate the market at the lower-cost domain, with its success in the higher end only coming with maturity. The process of maturing is, of course, much aided by the installation of a very large number of Windows systems�provided its vendor can provide the needed support and maintenance, since this exposes the system to a wide range of different situations.

Our thoughts must also encompass the �free software� phenomenon, as evidenced by Linux. Linux has the advantage of being essentially free at the point of acquisition; any problems it might have, compared to UNIX versions sold by the major manufacturers or by major software publishers will be in the level of support available. This risk is being mitigated however, as the same major manufacturers now include Linux in their catalogs and offer support and services for Linux as they do for their own systems. Independent software houses are also offering Linux support and services.

As we have emphasized before, a key element in choice of an operation system is the richness of the applications catalog associated with it. While the talk is encouraging, it remains to be seen just what the actual long term commitment of software vendors to Linux will be. While such vendors are most likely to be interested in the much larger marketplace offered them by Linux platforms, they are not likely to offer their applications in source form to the community.

For certain embedded and specialized systems, Linux has an undeniable attraction. Because such systems rarely are expected to run any extant application, but to execute some well-defined, application-specific applications, the richness of the application catalog is irrelevant. Qualifying such a system is eased by its natural closed character. The applications for such embedded systems may, themselves, be members of the world of free software� for example, the Apache web server, and the SAMBA PC file sharing package.


Market Evolution
As is often seen in the data-processing industry, a balancing effect had moved us from the centralized approach�terminals connected to mainframes� to a distributed approach, embodying minicomputers and of PCs. Unfortunately, the distributed approach, while providing more flexibility tended to give rise to inconsistencies in the company�s data and was hard to administer effectively. Now the world is swinging back towards a more centralized approach (at least as far as the management of data is concerned). �Upsizing� (or �server consolidation�) has the effect of increasing the average size of a server and concentrating a number of independent servers into a single server, whether it be a single large machine or a cluster.


Economic Considerations in the UNIX World
As in other areas, it is difficult for a systems vendor to bear the cost of development and maintenance for server-class UNIX systems if sales are weak. This leads to consolidations, concentrating the industry around ever-fewer UNIX versions. As the few remaining versions of UNIX differ, their uniqueness gives the UNIX market much of the flavor of the traditional proprietary market for high-end systems. And this, quite likely, will benefit Linux, which is not restricted at all in this manner.

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Source of Information : Elsevier Server Architectures 2005

64-Bit Architecture

The increase in size of both the data objects being operated on and physical memory and the need to hide disk and network access times by placing ever more information in the memory-based disk or network cache lead to severe pressure on the addressing ability of 32-bit processors and operating systems, which saturates at 4 GB. Some RISC processors�Alpha and PA from HP, SGI�s, MIPS, IBM�s Power, and Sun�s SPARC) support a much larger address space of 64-bits. Alpha was designed to be 64-bits right from its inception, while the others all began as 32-bit architectures and were extended later in life to 64-bits. In practice, Intel�s IA-32 architecture is limited to 32-bit addressing, although AMD has proposed a backwards-compatible extension to 64-bits. (It should be noted that, as defined, the IA-32 architecture allows addressing much more than 32-bits, but structured as 16,384 segments each of up to 4GB, but that no operating systems exist which make use of this feature). Intel�s new architecture, IA-64, is another architecture designed from inception to support 64-bit addressing. The first systems based on this architecture appeared on the market in the second half of 2001 with the Itanium processor (which had been codenamed Merced). The implementation of Itanium suffered so many delays and problems that many industry observers are of the opinion that the first commercially-attractive IA-64 implementation is Itanium�s follow-on, Itanium 2 (code-named McKinley). Systems based on, Itanium 2 appeared in the market in the second half of 2002.

Applications that can make good use of the vast address space offered by 64-bit addressing are primarily databases (particularly for decision support), with scientific applications and CAD programs also able to benefit. The advantages brought by a 64-bit architecture can be summarized as follow:

� The ability to address, per process and in virtual memory, a collection of objects representing more than 4 GB. This removes the need to manage the memory hierarchy explicitly within the application, and simplifies the ability to take advantage of the continuing increases in main memory size.

� The ability to support directly and efficiently files or filing systems whose size is greater than two to four GB.

� The ability to operate on large files placed directly in virtual memory. With a 64-bit address space, there is sufficient room for a substantial number of very large files to be placed mapped into virtual memory, where software can directly access them with load and store instructions rather than I/O operations and with the processor�s built-in address translation hardware doing all needed address translation. And, finally, the movement of data between memory and disk is handled automatically by the demand-paged virtual memory system itself.

� The ability to manage very large physical memories�larger than 4 GB. Memories of such size are principally used as cache for disk-based data; in particular, the performance of database management software depends in large part on their management of the memory hierarchy, which explains why database software generally takes responsibility for the management of disk caches. A DBMS can normally do better than a vanilla memory hierarchy manager, since the DBMS knows a lot about the data it is manipulating (whether a datum is data or index data, for example) and can act appropriately. Simply placing large amounts of (reused) data in memory provides a performance improvement, because it removes the need for the software to perform file-tomemory address mapping and also reduces I/O traffic.

It should however be noted that some 32-bit architectures (hardware and software system) can address physical memories of more than 4 GB and support file systems of more than 4 GB.

Clearly, to make full use of a 64-bit address space one needs�in addition to an appropriate processor�the necessary software: compilers, operating systems, applications. The vendors of 64-bit RISC systems (Compaq, Digital, HP, SGI, IBM, and Sun) offer such a suite. Some initiatives intended to adapt UNIX to IA-64 have fallen by the wayside. By mid 2004, Linux and Windows were the only operating systems planned for Itanium platforms and offered to system manufacturers, although there are 64-bit versions of AIX, HP-UX (available on both PA and Itanium for HP systems), Linux, Solaris, and Windows.

In the second half of 2001, IBM, with its z900 family of mainframe systems, introduced a 64-bit extension to the S/390 architecture, which had its roots in the S/360 system of the early 60s (with a 24-bit architecture). For servers, 64-bit architecture is a necessity, not a luxury. It acts as a foundation for the systems to support the changing needs of the application space and to take advantage of the opportunities offered by technology.

Source of Information : Elsevier Server Architectures 2005

Networks and Network Connections

As the Internet evolves, we can see specialization increasing in the portions of the systems providing communications support. In the mainframe era of the 1960s, communications were directly supported by the systems. This changed in the 1970s, as needs grew, and led manufacturers to produce semi-autonomous communications subsystems coupled to the main system. These were known as front-end processors, and examples include IBM�s 37xx series and Bull�s Datanet.

This trend increased with the rise of local area networks, with the emergence of a new generation of network equipment�routers, concentrators and so forth�that off-load a number of chores from the servers.

Nowadays, we do not expect a server to directly support a variety of communications interfaces, but rather to provide a number of high-bandwidth pipes that carry requests for it to operate on the data it owns.

We expect this trend to continue, especially with convergence resulting in the same network carrying voice (and video) along with data, from the point of view of provisioning sufficient physical resources as well as from the IP point of view. Forecasts suggest a continuing significant increase in data traffic, with voice traffic stagnating; thus, the effects of this convergence will likely be felt more in the telephony industry (makers of automatic telephone exchanges and switches) than in the data-processing industry.

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Increased use of multimedia will impose further demands on servers, because of the need to observe and guarantee temporal properties. This might suggest deployment of specialized realtime operating systems as well as use of special peripherals, such as disks optimized for this type of use. The industry has at its disposal a number of technologies, particularly optical, which will allow it to support demand; increasing bandwidth; reducing latency; the address space increase offered by IPv6; the concept of quality of service, and so on.

A key issue, though, is driving new uses that will themselves make use of the possibilities available and allow these technologies to be deployed.

Cisco, the world leader in networking equipment, envisages the emergence of the intelligent network, whose components are:

� Interconnection with proprietary networks like SNA, DSA or others;

� Broadcast or multicast facilities, allowing one message to be sent to many destinations

� Video services (both video conferencing and video-on-demand)

� Cache services

� Administration

� Voice-related services

� QoS (quality of service)-related services

� Security services

Looking at these a little deeper:

� Interworking with proprietary networks is a necessity while these networks exist

� Some applications would benefit from a multicast capability�one message with multiple recipients (examples of such applications include videoconferencing, updating workstation software, Internet �push� technologies, information replication, and more)

� Expect videoconferencing to grow, since it can reduce travel and thus reduce costs and the polluting side-effects of vehicle usage; however, it is a new form of interaction, and there will need to be a learning curve as individuals adapt to it (video on demand, except for specialty niches such as within hotels, should grow at a much lower rate)

� Caching data in the network improves access to information

� It is difficult to overemphasize the requirements for good administration and security in networks

� The concept of QoS appeared a few years ago, and still needs time to develop fully. It is a fundamental parameter for the usability of a system. In use, the quality�in terms of bandwidth, or latency, for example�of a connection is negotiated, and then the network guarantees that level while the connection is open

When a number of disks are assembled within a single enclosure, but without any special organization (such as RAID) being implemented, the collection is known as JBOD (Just a Bunch of Disks).

Source of Information : Elsevier Server Architectures 2005

Intelligent Disks

We will now look at yet another proposal from researchers at the University of California at Berkeley, a place with a high output in the field of innovative architectures. Their proposal is to do with making good use of the processing capabilities embedded with each disk drive; they call it Intelligent Disks (or IDISKs).

In the early days of magnetic peripherals, the interface provided facilities closely matched to the operations the disk mechanism could naturally perform. This changed; in the 1960s, with processing power causing a system bottleneck, disk units with autonomous data-handling capabilities began to appear, with a concomitant increase in the level of abstraction supported by their interfaces. An example from IBM in the S/360 family was the ckd interface, which, for example, allowed the system to delegate to the disk a key-based search for a record.

The economics of minicomputers and then microprocessors made processing power cheap enough that intelligence began to migrate back into the system proper, and we saw the emergence of standard low-level disk interfaces like SMD and ESDI. The growth of complexity in the peripherals drove the existence of a higher-level interface, SCSI. Implementing SCSI more or less requires a microprocessor and supporting memory, to provide protocol support, cache, local management of the peripheral, management of read/write head positioning, error management, buffer space for SCSI bus transfers and so on. Current technology already makes it possible to integrate, low cost, and low power processing/memory and interface electronics directly with the peripherals themselves, along with system interface support (such as FC-AL). The idea behind intelligent disks is to make greater use of this embedded intelligence, allowing both off-loading of the server and greater computational concurrency. We note here the balance swinging back: new technology allows us to effectively re-implement old ideas.

Various levels of functionality may be envisaged for intelligent disks.; Examples include:

� Off-load database management software, along with necessary supporting OS functions, in a share-nothing architecture implemented across the disks themselves

� Off-load some database management functions onto the disks�for example, searches and joins, with the control of these operations being done by the server-resident DBMS

� Off-load file system activities�for example, optimizing a string of commands by reordering them in the disk to minimize head movement

While there is little quantitative information available for the benefits this approach can bring, the real problem is standardization. Indeed, widespread deployment of intelligent disks would mean that the most widely used software (from basic file systems with simple access methods, such as those offered by Windows and Linux, all the way up to DBMSs) would be adapted to such machinery. This requires agreements between the players behind this software and the disk manufacturers; an agreement between the disk manufacturers is in the realm of the possible, and is in any case a prerequisite for any larger agreement between software vendors and the disk manufacturers.

These latter possibility seems more remote; we can easily observe that historically, DBMS manufacturers have avoid using the magic features of any system platform, preferring to use extremely low-level interfaces so that they could be certain that execution of vital functionalities is under their control and could therefore be guaranteed across platforms. This view also simplifies porting across platforms and reduces support and development costs for the DBMS.

Source of Information : Elsevier Server Architectures 2005

Disk Evolution

We expect the rate of improvement in basic technology for disks�storage density and access time�to slow down. Improvements in the architecture of disks and storage subsystems will be able to compensate somewhat for this slowing, particularly for the high-end products, which is where we concentrate our discussion.

Image, inspired by [MOO99], summarizes some predictions about disks and storage subsystems.

A few comments are in order, including the observation that the suggested order of events is not to be taken literally.

� The first changes suggested are to do with improvements in the bandwidth of the system interface (with FC projected at 2x2 Gb/s in 2002), or with improvements in bandwidth between the disk units themselves and the disk subsystems (using FC-AL or SCSI at 360 MB/s in 2003), as well as the projected increase in disk capacity (to beyond 100 GB) and rotational speed (moving first to 10,000 rpm and then on to 15,000 rpm). Increasing disk rotational speed improves average access time (which is the time for half a turn of the disk).

� Using high-level interfaces such as SCSI or FC-AL implies the use of a 32-bit microprocessor and a few megabytes of memory in the disk units; the provision of memory allows the disks to provide a cache in a totally transparent manner.

� A spread in the use of data compression is seen. This allows economies in several aspects of disk usage�not only is effective data capacity increased, but also effective bandwidth is increased and latency reduced by the degree of compression attained�at the cost of some processing to effect the compression and decompression. Given the very favorable improvements expected in price-performance for microprocessors, the computational burden imposed by this extra processing should easily be supported, whether in the server proper or in processors embedded in the disk subsystem.

� Physical sharing of storage between servers is currently possible at the subsystem level, and is the basis for SAN.

� As the intelligence in the subsystems grows, it is possible to give them the responsibility for higher-level activities, such as implementing backup and restore: the system initializes as needed, and then the peripheral does the work autonomously.

� Sharing storage at the logical level is significantly more complex a problem than physical sharing, since it means that two different systems (different processor architecture, operating system and data manager) are sharing logical data. Because of the wide diversity of systems and because in many cases the stored data is managed by a DBMS, it is reasonable to suppose that logical sharing is not at all widespread (in heterogeneous systems); it is much simpler to base server cooperation on a client/server-like behavior between applications.

� With disk technology improvements, it is possible for a disk manufacturer to offer multi-disk subsystems, operating as a RAID system and/or as a SAN subsystem; that is, disk manufacturers could become players in the storage world. This would likely hurt the established storage vendors in the same way that Intel moved from being a mere chip manufacturer to a specifier and supplier of systems.

� Data availability requirements and risk avoidance are likely to make remote backup increasingly common, and perhaps commoditized. This could drive a market for companies offering backup storage, with network exchanges taking the place of physical exchanges of magnetic cartridges.

� We can then envision an increase in Fibre Channel bandwidth, and the arrival of 500 GB capacity disks.

� When a system's overall performance is dependent on the performance of its I/ O, the overall performance is (as we have noted previously) liable to drop as improved disk technology becomes available, since as capacity increases the number of physical disks needed is reduced, automatically reducing the amount of parallelism available to the I/O system. Having multiple independent read/write channels on a single disk could claw back some of this concurrency, by more or less doubling parallelism at the disk level.

The last point on the graph is a disk built from DRAM, sometimes called a RAM Disk or a Solid State Disk. For many years, some observers have repeatedly predictied the crossing of the cost prices for DRAM and magnetic storage, and consequently the replacement of disks by DRAM. Beyond the projected cost benefits, the driving force behind this movement is the simple fact that DRAM is orders of magnitude faster than magnetic storage (perhaps 40 microseconds in place of 10 milliseconds). However, cache technology works for disk accesses as well, and a disk subsystem marrying a traditional magnetic storage device to a large DRAM cache can approach the performance of a pure DRAM disk without having to overcome the key issues of cost (since the cost curves have still not crossed and show no immediate signs of doing so) and volatility.

The volatility issue is real; DRAM is volatile�cut the power for more than a rather short interval and all the information is lost. To avoid this, one can provide a battery to keep power on at all times, or look for a better technology. The semiconductor industry is well aware of this and has been developing a number of promising technologies which marry silicon and magnetic effects. Motorola's MRAM [GEP03] seems to be a leader, although more directed at embedded memory than commodity memory chips; IBM's TMJ-RAM (Tunneling Magnetic Junction�Random Access Memory) is also worthy of mention. These technologies promise most interesting benefits: MRAM can be roughly characterized as having the density of DRAM, the access times of a mid-range SRAM, non-volatility and the ability to be rewritten an indefinitely large number of times. Even if costs do not reduce enormously, memory chips built from these technologies could be beneficial for applications requiring very high bandwidths, or for specialized roles such as journaling transactions�that is, recording the journals which track transaction-based changes in a non-volatile memory.

Source of Information : Elsevier Server Architectures 2005

Network Communication Technologies

Within a system, multiple communications networks meet�from a chip handling internal connections all the way up to long-distance networks or networks formed from I/O buses and local networks. We will attempt to put the sundry communications technologies into perspective by organizing them by their potential data bandwidths and the distance they are intended to cover. What is usually covered by a discussion of networks is just one part of the whole picture.

The attach image, with no claim to completeness, lists various technologies classified by their distance (point-to-point) and bandwidths.

The very highest bandwidths, over extremely short distances, are the internal communications within a chip.

We then encounter a number of technologies which we can group together under the rubric of intrasystems networks, for which the acronym SAN has been used; in that context it meant System Area Network. However, nowadays the use of the acronym has been preempted to refer to network storage, when it means Storage Area Network. To minimize confusion, we shall adopt this latter meaning for the acronym. In the category of intrasystems networks we find:

� Systems buses, connecting processors to memory and I/O, are characterized by bandwidths of several gigabytes per second and distances in the 10-20 cm range�less than a foot

� I/O buses, such as PCI, which connect the processor-memory complex to I/O controllers. InfiniBand might replace PCI for this usage in mid-range and high-end servers. Connecting the processor-memory complex to the I/O subsystems, which would themselves likely still be built around PCI or a derivative

� Connections between I/O controllers and the peripherals themselves, using SCSI or FC-AL

� Connections between the processor-memory complex and a peripheral subsystem, such as disk or tape susbystems or a communications concentrator. Fibre Channel is the current prime example, and it may be joined by InfiniBand. HPPI (High Performance Parallel Interface) offers the same level of performance as Fibre Channel, but its use in practice is limited, essentially, to supercomputers

Beyond the intrasystems networks we find the local area network category:

� Ethernet, offering three classes of bandwidth: traditional Ethernet at 10Mbits/ second, fast Ethernet at 100 Mbits/sec (both these are very widely used) and gigabit Ethernet at 1 Gbit/second, which is finding its place in the market

� Token Ring at 4 to 16 Mbits/sec, which has an advantage over Ethernet in that it offers deterministic behavior. However, it has not had the same marketplace acceptance as Ethernet, probably because it is not an open technology and because of higher prices

� Fibre Channel and FDDI (Fibre Distributed Data Interface) make an appearance in this category as well, often as a concentrator of lowerspeed local area networks (such a network is referred to as a backbone)

� ATM has pretensions in the field of local area networks as well, with an emulation of a LAN named Lane (for LAN Emulation)

We then come to metro area networks, which are networks within a single city using technologies such as:

� Fibre Channel
� DQDB (Distributed Queue Dual Bus), which uses a pair of unidirectional bus connections
� FDDI, based on a token-ring technique
� ATM

And finally we see the category of long-distance or wide-area networks with technologies such as SONET (Synchronous Optical NETwork), and SDH (Synchronous Data Hierarchy) which are standards (ANSI for SONET), and International Telecommunications Union (ITU�once known as CCITT). SONET and SDH both carry ATM packets. For private lines, Frame Relay is also worth mentioning; it extends the capabilities of X25.

In the image, we also show two technologies used to connect users to telecommunications networks: ADSL (Asymmetric Digital Subscriber Line) and HDSL (High Bit Rate Digital Subscriber Line), are standards in this area. They make it possible to sharply increase bandwidths using existing copper telephone connections, giving up to 52 Mbit/sec for distances up to 300 meters (a bit over 300 yards) and even 1.5 Mbit/sec at distances up to 3 kilometers (around 2 miles).

Alongside the convergence of the different technologies in the areas of distance and bandwidth, we also see a convergence between local and wide area networks. As an example, ATM technology is as well-suited to LAN usage as it is to WAN. And it incorporates the concept of quality of service, guarantee a user�once a connection is granted�a quality of service (in guaranteed bandwidth, for example) for the duration of that connection.

However, the largest portion of installed networks are IP networks; this domination can only be extended with the advent of the new IPv6 version of the protocol, which considerably extends the address space of an IP network. Given IP's commanding position, any new network technology must support IP if it is to succeed.

Source of Information : Elsevier Server Architectures 2005

Disabling Services with the Services Utility

There are dozens of services in Windows 7, you can start disabling the services that are not needed for your computer usage and that are slowing down your computer boot process. To do this, you will use the Services utility that enables you to start, stop, and configure Windows 7 services.

Before you begin changing your service setup, set a system restore point � a configuration where you can easily restore your system. However, be careful when you restore from restore points. Any applications or files that were created after the system restore point will be deleted when reverting back to an earlier restore point.

The Services utility is included in all versions of Windows 7, but is hidden away. Disabling a service with the Services utility is easy. Just complete the following steps:

1. Click the Start button, type services.msc in the Search box, and press Enter. This will start the Services utility.

2. When the Services utility has loaded, you will see a list of all the services available on your computer and the ones that are started. Before you can disable a service from starting up, it is best to stop it first. Scroll through the list of services until you find the name of the one you want to disable. Right-click the service name and select Stop.

3. When the service is stopped, right-click the service again and select Properties. On the General tab, look for the Startup Type drop-down box. Click the arrow on the drop-down box and select Disabled.

4. Click OK. From now on, the system will not start the service during boot, which should speed up your system start.

Bare-Bones Service Configuration
To get the maximum performance out of your system, you have the option of disabling all the services on your computer that are not critical to the system. This will take away a lot of the nice features and conveniences of Windows, but you would have a much faster machine. The following is a list of all services that started by default in Windows 7 and can be safely disabled:

� Application Experience
� Application Information
� Background Intelligent Transfer
� Base Filtering Engine
� Bluetooth Support
� Desktop Window Manager Session Manager
� DHCP Client
� Diagnostic Policy
� Diagnostic System Host
� Distributed Link Tracking Client
� EAPHost
� Function Discover Provider Host
� Group Policy Client
� IKE and AuthIP IPsec Keying Modules
� IP Helper (if you are not connected to an IPv6 network)
� Microsoft iSCSI Initiator Service
� Microsoft Software Shadow Copy Provider
� Multimedia Class
� Network Connections
� Network List
� Network Location Awareness
� Offline Files
� Policy Agent
� Portable Device Enumerator
� Program Compatibility Assistant
� Routing and Remote Access
� Security Center
� Server
� SSDP Discovery
� Superfetch
� Tablet PC Input (if you do not have a Tablet PC)
� TCP/IP NetBIOS Helper
� Terminal Services
� Themes
� WebClient
� Windows Audio
� Windows Audio Endpoint Builder
� Windows Defender
� Windows Error Reporting Service
� Windows Firewall
� Windows Management Instrumentation
� Windows Search
� Windows Time
� Windows Update
� WinHTTP Web Proxy Auto-Discovery
� Workstation

Recommended Service Configuration
The barebones system service setup is great for optimal performance, but you are eliminating a lot of the cool new features that make Windows 7 cool and new. Check out my list of recommended services to disable:

� Bluetooth Support
� DHCP Client (assign yourself a static IP address)
� Diagnostic Policy
� Diagnostic System Host
� Distributed Link Tracking Client
� EAPHost
� Function Discovery Provider Host
� Group Policy Client
� IKE and AuthIP IPsec Keying Modules
� IP Helper (if you are not on an IPv6 network)
� Microsoft iSCSI Initiator Service
� Offline Files
� Policy Agent
� Routing and Remote Access
� SSDP Discovery
� Tablet PC Input
� WebClient
� Windows Search
� WinHTTP Web Proxy Auto-Discovery

Disabling these least commonly used services provides a good balance between saving boot time while keeping the cool new Windows 7 features and application compatibility.

Source of Information : Windows 7 Tweaks 2010